MAYDAN, Iraq (Reuters) -- Kurdish troops say they lost many men trying to bring security to a volatile, ethnically mixed part of Iraq only to be ordered out by the central government.

A brigade of about 2,000 Kurdish Peshmerga forces withdrew on Monday from some towns in Diyala province they had been patrolling and moved to a part of the province bordering the largely autonomous enclave of Iraqi Kurdistan.

They had come under pressure from the central government, which is seeking to tighten its grip on Diyala and other parts of northern Iraq where Arabs and Kurds live side by side.

Some Arabs and Turkmen accuse the Kurds of trying to extend their influence into areas of Iraq beyond their autonomous homeland.

Dozens of Kurdish soldiers looked tired and pale-faced after hours spent marching some 40 km (24 miles) to an old castle in the town of Maydan, after leaving the town of Qarah Tappah to be replaced with regular Iraqi army and police units.

Some slept on the few available bunk beds, others cleaned their AK47s and machineguns or propped up mortar tubes.

"We were fighting terrorism and our goal was to bring stability," said the brigade commander, Brigadier-General Nadhim Najim Ahmed, as he sat in his office in the castle wearing a traditional Kurdish robe with a thick turban.

"We gave numbers of martyrs to get this goal. Now we are afraid that Kurds could be targets for revenge attacks by the terrorists," he added.

"During the period we served there, we did not discriminate between people as Arabs, Kurds and Turkmen."

Diyala province, home to Sunni and Shi'ite Arabs, Kurds and Turkmen, has become as flashpoint for ongoing violence as the rest of Iraq grows more stable.

Some Peshmerga felt their contribution to helping tackle that violence had gone unheeded.

"During our deployment there, in spite of the serious threats, we were happy because we felt we had secured the lives of people in these areas," said Shakhwan Hussain, a non-commissioned officer in the brigade.

The Iraqi government was not available to comment but Prime Minister Nuri al-Maliki has pledged to put Iraq's security firmly in the hands of the central authority, saying only the Iraqi military and police have the right to bear arms in Iraq.

By Sherko Raouf