A wave of arrests of Sunni Arab guards in a Baghdad district has spooked other units who helped rid the capital of al Qaeda, and who fear the Shi’ite-led government is out to get them for their Sunni insurgent past.

In interviews on Thursday in several Baghdad districts, U.S.-backed Sunni Arab patrolmen who switched sides to fight al Qaeda in 2006 were dismayed at arrests of fighters loyal to Adil al-Mashhadani, head of a patrol unit in Fadhil, central Baghdad.

Mashhadani was seized on Saturday in a raid that sparked deadly clashes between his supporters and Iraqi security forces.

Major-General Mizher Shaher Nusaif, operations commander for eastern Baghdad, said 36 had been arrested so far, but 14 of those were likely to be quickly released.

Many of the fighters, who once numbered around 90,000 across Iraq, have long feared they would be arrested for past crimes after the government took control of their programme from U.S. forces late last year. The U.S. military, though, says Mashhadani was wanted for a spate of recent crimes.

How the government handles the guards it once fought is a major test of reconciliation after years of sectarian bloodshed between Sunnis and Shi’ites. Deep mistrust remains.

With his AK-47 slung over his shoulder and a pistol strapped to his jeans, Wisam Faris, 24, kept a keen watch on the streets of west Baghdad’s Ghazaliya district. He said he felt betrayed.

“We helped the American and Iraqi forces maintain security in Baghdad, and now they are arresting us. Of course we are afraid. Why are they doing this now?” he said bitterly.

“We did a great job maintaining security and they did nothing for us. We haven’t been paid for two months,” he added.

Called Awakening Councils — Majalis al-Sahwa in Arabic — the units led mostly by Sunni Arab sheikhs and comprising former insurgents helped drastically cut violence in Baghdad, western Anbar province and elsewhere after U.S. forces recruited them.

“Are they all angels?” said Interior ministry spokesman Abdul Karim Khalaf. “No. No one is above the law.”

The U.S. military said it had handed over the last 10,000 fighters to Iraqi control. It said administrative hiccups that had delayed their wages had been fixed as the government secured emergency funds to pay them, starting on Thursday.

Sahwa leaders in Anbar said they supported the arrest of Mashhadani. Yet even those in Baghdad who agreed with weeding out the criminals amongst them urged caution.

“This is not the appropriate time to be arresting. Security in Baghdad is not stable,” said leader Khalil Ibrahim, shaded by the giant domes of a mosque in Adhamiya, north Baghdad, and surrounded by dozens of armed men.

Diplomats say the level of Sunni Arab resentment at their loss of dominance in Iraq after decades of being the ruling elite should not be underestimated, and so the treatment of the Awakening Councils by the Shi’ite authorities is crucial.

Western military officials, however, say they are confident that Mashhadani’s arrest was a matter of law enforcement, and not a case of settling sectarian scores.

“Mashhadani was arrested because there were standing warrants out for him … This is not any indication of some sort of campaign (against the Sahwas),” said Lieutenant General Lloyd Austin, the U.S military’s second in command in Iraq.

Shujaa al-Aadhami, a leader in Ghazaliya, was not convinced.

“Two of my people were arrested last week. I don’t think these arrests are about law. They’re playing a game … and it’s not going to help reconciliation,” he said.