Sheikh Abdul Sattar Abu Risha (file photo)

Al-Qaida in Iraq has claimed responsibility for Thursday's bomb attack that killed Sunni tribal leader Sheikh Abdul Sattar Abu Risha -- a key U.S. ally in Iraq.

The group made the claim in an Internet statement Friday.

The attack on Abu Risha near his home in Ramadi in al-Anbar province has been widely blamed on al-Qaida in Iraq.

Mourners accompany the coffin of Sheik Abdul Sattar Abu Risha in Anbar province in the provincial capital of Ramadi, 14 Sep 2007

Earlier Friday, mourners at Abu Risha's funeral called for revenge. Iraqi police and U.S. military vehicles lined the route of the funeral procession.

Last year, Abu Risha organized Sunni Arab clans under the umbrella of the Anbar Awakening Council to fight al-Qaida in Iraq. He was killed a little more than a week after meeting in Anbar province with President Bush.

U.S. and Iraqi officials credited Abu Risha with helping stem the violence in the province.

In other news, the U.S. military says a roadside bomb blast killed four U.S. soldiers in Diyala province, east of Baghdad.

In the northern town of Baji, Iraqi police say a suicide truck bombing killed at least seven policemen.

South of Baghdad, assailants shot and killed three people, while in the city of Hillah, an attack on the home of a colonel left one guard dead.

Some information for this report was provided by AFP, AP and Reuters.