BAGHDAD (UPI) -- Siege warfare continued taking its toll in Syria last week as coalition forces conducted attacks against Islamic State revenues in Iraq.
IS militants reportedly abducted at least 400 people in the eastern province of Deir Ezzor on Sunday. The move came after a Saturday assault into northwestern portions of the provincial capital, where several government-held areas are under siege by the militants. Activists said at least 135 people -- 85 civilians and 50 pro-government fighters -- were killed in the attack, which saw IS forces utilizing a mixture of suicide bombers and infantry. Syrian state news put the number of dead at 300. The prisoners were reported to be family members of pro-government fighters.
The Syrian Observatory for Human Rights said IS controls at least 60 percent of Deir Ezzor, which is one of several locations in Syria under siege. Forces loyal to Syrian President Bashar al-Assad have encircled multiple areas around the capital Damascus, including portions of eastern Ghouta, the western suburb of Darayya and the nearby mountain towns of Zabadani and Madaya. Rebel forces, on the other hand, are besieging the villages of Foah and Kefraya in Idlib province.
In northern portions of Latakia province on Sunday, government forces captured two villages and surrounding hills, as well as four nearby mountains, according to Syrian state news. Pro-Assad forces have been on the offensive in Latakia and other areas of northwestern Syria in recent months following Russia's intervention on behalf of Assad in late September. On Sunday, SANA reported rebel forces in the area retreated to positions near the town of Rabiaa on the Turkish border. The previous Monday, pro-Assad forces captured Salma, a strategically important town in Latakia overlooking portions of a rural mountainous region known as Jabal al-Akrad. By Wednesday, SOHR reported, government forces -- including Russian advisers and Lebanese Hezbollah fighters -- began advancing from Salma into the surrounding hills.
Also on Sunday, activists said airstrikes killed at least 40 people, including eight children, in the de facto IS capital of Raqqa, but it was not clear whether the strikes were conducted by Russia, the Syrian government or the U.S.-led coalition -- all of which fly sorties over the city. The U.S. Department of Defense said coalition aircraft conducted airstrikes against Raqqa on both Jan. 16 and Jan. 17 but reported the strikes targeted IS positions.
In the nearby Aleppo province on Thursday, rebel forces captured the town of Khan Toman, killing at least 21 government troops and allied militiamen, according to SOHR. The village fell amid three-way fighting across the province among the Syrian military, an alliance of rebel factions and IS. Activists said government forces were advancing against IS in Aleppo's east as IS simultaneously seized the village of Ghazal from Turkey-backed rebels the same day Khan Toman fell.
Bloody back-and-forth fighting across Syria is overshadowing Vienna peace talks scheduled for Jan. 25.
The conflict's many actors are seeking battlefield gains in an attempt to strengthen their positions leading up to the talks. The Syrian military, backed by Iran and Russia, launched a series of counter-offensives following the addition of Russian airstrikes to its arsenal on Sept. 30. A fragmented series of rebel alliances are meanwhile vying for control in various portions of the country, including a U.S.-backed rebel coalition of Kurds, Assyrians and Arabs in Syria's northeast, while IS forces attempt to maintain and expand lands comprising their self-declared caliphate.
Several major rebel groups met in Saudi Arabia last month to hammer out a unified framework for the Vienna talks, but Kurdish rebel cells such as the YPG and militants with the Nusra Front, a rebel group linked to al-Qaida, were not invited.
However, the U.S.-backed rebel coalition known as the Syrian Democratic Forces held their own conference on Dec. 11 in the al-Hasakah province, announcing the formation of a political wing known as the Syrian Democratic Council.
The Syrian government has said it will join the Vienna talks but wanted to know in advance whether they would be attended by "terrorist groups" -- a distinction used broadly by Damascus, as well as Moscow, in reference to all of Syria's opposition. Previous attempts at peace talks collapsed in the face of Syrian government intransigence over allowing rebel cells a seat at the negotiating table.
Further complicating the matter is the recent deterioration of relations between Saudi Arabia, which supports much of the Sunni opposition in Syria, and Iran, which provides open backing for the Alawite government of Assad. The Saudi execution of a revered Shia cleric earlier this month was followed by protesters sacking the Saudi embassy in Tehran, prompting multiple Sunni states, including Saudi Arabia, Bahrain and Sudan, to cut ties with Iran.
Still, British United Nations Ambassador Matthew Rycroft said Thursday he is "optimistic that 2016 will be the year when finally we turn this around."
"Look, we've known all along that Saudi Arabia and Iran have very different and opposite views on the future of Syria and on so many other issues," CNN quoted him as saying. "But the Vienna process has as one of its strengths the fact that those two countries are both inside that single tent."
Iraqi security forces said they killed at least 40 IS militants Sunday in eastern portions of Ramadi, the capital of Anbar province. Police told IraqiNews.com the clashes occurred in the city's Juwiba and al-Sedikiya neighborhoods, and that officers disarmed 16 improvised explosive devices and destroyed six defensive positions and five vehicles used by the militants.
The center of Ramadi fell to the Iraqi military and allied Sunni tribal fighters late last month after a costly assault, and government forces are still clearing small groups of IS militants from various neighborhoods.
IS has reportedly re-oriented its efforts west of the city, launching multiple failed attacks against Haditha and Barwana. Security forces repelled such an attack on Saturday, Iraq's interior ministry said.
In Baghdad on Sunday, a bomb attack in the southern Mahmudiya district killed at least two people and injured nine, the interior ministry said. The attack came six days after IS militants conducted a gun and bomb assault against a shopping mall in a predominantly Shia area of Baghdad, killing 18 people.
Diyala province saw further attacks against Shia Muslims; on Monday twin blasts cut through a cafe in Muqdadiya, killing at least 20 people -- mainly members of the Hashid Shaabi, an anti-IS umbrella group of Shia militias that enjoys support from Iran's Quds Forces. Some of the fighters reportedly launched reprisal attacks against local Sunnis, performing summary executions and burning shops, mosques and homes.
The same day, coalition aircraft dropped two 2,000-pound bombs on a bank used by IS militants in Mosul, capital of Nineveh province. The resulting explosions incinerated millions of dollars garnered through black-market oil sales and extortion, officials said. Five days later, Kurdish officials said IS militants executed at least 25 people attempting to escape Mosul, which the militants have controlled since July 2014. Four women and six children were among the dead.
The Iraqi government seeks to evict IS fighters who seized large portions of northern and western Iraq in 2014. Last year, Baghdad saw success in cities such as Tikrit and Sinjar but also reverses in places like Ramadi, where Iraqi security forces retreated from an IS assault in May. The Iraqi military regained the city late last month after suffering heavy casualties and continues to clear eastern neighborhoods where small groups of IS fighters have stalled a complete victory.
IS, meanwhile, has redirected efforts in western Anbar, conducting multiple assaults on Haditha and Barwana, using a favored tactic: coordinated thrusts of infantry and car bombers. Suicide bombers have also wreaked havoc on soft targets around Baghdad and other parts of the country as the U.S.-led coalition continues with an air campaign against IS that has been ongoing since August 2014.
"May is when [IS] reached their culminating point of offensive operations," Pentagon spokesman Army Col. Steve Warren said earlier this month. "Since then, all they've really managed to do is lose ground."
Multiple areas of Anbar province -- notably the IS-held city of Fallujah, where U.S. troops fought two bloody battles against insurgents in 2004 -- have yet to be cleared, however, and still looming is the main objective of Baghdad and the U.S.-led coalition: Mosul.
"Our campaign plan's map has got big arrows pointing to both Mosul and Raqqa," Military Times quoted U.S. Defense Secretary Ash Carter as saying at Fort Campbell, Ky., on Wednesday.
Carter met with top military leaders at U.S. Central Command in Tampa, Fla., on Thursday to discuss details of an accelerated anti-IS campaign.
The strategy reportedly calls for Kurdish Peshmerga forces to push in from the north and east of Mosul while the Iraqi military assaults from the south. Coalition aircraft will provide fire support. The Iraqi military will also attack west from Ramadi toward the Syrian border.
In Syria, a similar plan is being developed to capture the IS capital of Raqqa. U.S.-supported rebel groups in northeastern parts of the country, such as the SDF in al-Hasakah province, are already capturing territory north of the city in preparation for an eventual assault against the IS stronghold.
Much of this plan, however, relies on Turkey sealing its border with Syria in order to cut off the militants' main supply line to the outside world.
Carter said recent coalition battlefield gains have "allowed us to accelerate the campaign, gather momentum, and pressure [IS] in Iraq and Syria on more fronts than at any other point in the campaign."
"This pressure is having an effect against [IS]," Carter told reporters. "It is also generating additional opportunities to further accelerate the implementation of the campaign."
Alongside the targets of Mosul and Raqqa is IS revenue. The Monday airstrike against an IS bank in Mosul came amid Operation Tidal Wave 2, a coalition effort targeting IS funding, mainly through airstrikes against oil infrastructure. In one such strike in November, the coalition said it destroyed more than 280 IS oil trucks in Syria's al-Hasakah province.
"We believe these airstrikes are markedly degrading one of [IS]'s most important sources of funding," Adam Szubin, the U.S. Treasury's acting under secretary for terrorism and financial intelligence, said last month.
Threatening ultimate success in Iraq, however, is the specter of sectarian division. Experts say the Iraqi military's collapse in 2014 -- when 30,000 armed and trained Iraqi troops retreated from 800 lightly-armed IS militants attacking Mosul -- was rooted in the sectarianism of the Shia-dominated government in Baghdad.
The purging of Sunnis from several government and military command positions by former Prime Minister Nouri al-Maliki alienated Iraq's minority Sunni populace, which sympathized with attacking IS fighters. It also ensured that inexperienced Shia cronies, rather than merit-based candidates, were in charge of Iraq's U.S.-trained and -equipped military.
When Tikrit fell to government forces last year, the Iraqi military relied heavily on U.S. air power and the Hashid Shaabi. U.S. officials denied working with the Shia militas, which had to be pulled from the majority-Sunni city following reports of extrajudicial killings, arson and looting.
A Hashid Shaabi spokesman promised to punish those responsible for the recent reprisal attacks against Shiites in Mahmudiya, but such incidents could threaten to push moderate or undecided Sunni Arabs into alliance with IS.