''There's a fear that when (the Interior Ministry) comes in, it may not be on a legitimate mission, unless they're with us," said Lieutenant Colonel Greg Butts, commander of the 2d Battalion, 506th Regimental Combat Team, 101st Airborne Division that oversees Dora.
Gaining public acceptance of the Interior Ministry commandos, recently renamed the National Police, has become a priority for US forces. American commanders plan eventually to hand over counterinsurgency operations in large swaths of Baghdad and other cities, including Samarra, to the Interior Ministry as part of the broad effort to move US troops into a background role -- and eventually out of Iraq.
But both US and Iraqi officers say winning public trust will take time.
Sunni leaders in Dora have even warned US commanders that they will fire on commandos who try to approach their homes, Butts said.
It is not an idle threat. Earlier this month, residents in the Sunni neighborhood of Azamiyah battled for two days against Iraqi forces, believing they were Shi'ite death squads. As many as 13 people were killed
Suspicion does not run as deeply toward the Iraqi Army, a better-trained force controlled by the Defense Ministry, which is run by a Sunni. However, Interior Ministry commandos play a major role in many counterinsurgency operations, especially in the Baghdad area where sectarian tensions run high.
Many Sunnis consider them indistinguishable from Shi'ite militias.
Last week, US Ambassador Zalmay Khalilzad warned that militias form the ''infrastructure of civil war" in Iraq. The Iraqi government must incorporate them into its armed forces so that their loyalty is to the state, not their sectarian leaders, he said.
But determining a commando's true allegiance is not easy.
During a recent patrol in Dora, one commando turned on his cellphone to proudly display an image of Moqtada al-Sadr, the radical anti-American cleric. Sadr's powerful Mahdi Army of militiamen is accused by Sunnis of attacking their mosques in retaliation for the Feb. 22 bombing of a Shi'ite shrine in Samarra, north of Baghdad.