KUT, Iraq &#8212 American commanders in southern Iraq said Shiite sheiks are showing interest in joining forces with the U.S. military against extremists, in much the same way that Sunni clansmen in the western part of the country have worked with American forces against al-Qaida.

Sheik Majid Tahir al-Magsousi, the leader of the Migasees tribe in Wasit province, acknowledged tribal leaders have discussed creating a brigade of men trained by Americans to bolster local security, as well as help patrol the border with Iran.

The movement by Shiite clan leaders offers the potential to give U.S. and Iraqi forces another tactical advantage in curbing lawlessness in Shiite areas. It also would give the Americans another resource as they beef up their presence on the border with Iran, which the military accuses of arming and training Shiite extremists.

Similar alliances with Sunni tribes in Anbar province helped break the grip of groups such as al-Qaida in Iraq and were widely cited in Washington hearings as a major success this year.

U.S. officials at the heart of the effort hope to tap a wellspring of public frustration with militias and criminal gangs to recruit the tribal volunteers, although they stress it is still in the early stages.

In Anbar, the goal of the Sunnis was to drive al-Qaida in Iraq away from towns and villages because of the terror movement’s attempt to impose a rigorous Islamic lifestyle.

In Wasit, which borders Iran, the goal is to rein in armed Shiite groups which are locked in a power struggle that is making life intolerable for ordinary people.