"These terrorist supplies have been used to attack the Iraqi and coalition forces, and the local population in Diyala to destabilize the area," said Col. David Sutherland, commander of the 3rd Brigade Combat Team of the 1st Cavalry Division. "However, the initiative and ability to seize every opportunity to aggressively attack the terrorists will actually destabilize the terrorists."

So far, Sutherland has led his unit as well as those from the Iraq Army's 5th Division in killing around 20 suspected Sunni insurgents and detaining a similar number. He said eight caches of weapons have been found and several Islamic State of Iraq strongholds were raided.

"The ISF [Iraqi security forces] continues to improve as we conduct these operations together, and the people gain confidence in their security forces' ability to take the fight to the enemy and secure the population," Sutherland said.

The Islamic State in Iraq has been deemed an umbrella group that includes Al Qaida. Islamic State claimed responsibility for the Tal Afar twin truck bombing attack on March 27 in which a record 152 people were killed and 185 injured.

"These horrific attacks demonstrated Al Qaida's complete rejection of respect for life itself, and the coalition joins Iraqi leaders in condemning these latest acts of cold-blooded murder," U.S. military commander in Iraq, Gen. David Petraeus, said.

The Tal Afar bombing prompted a revenge campaign by Shi'ite militias, including police officers, against Sunnis. On March 28, at least 72 Sunnis were executed.

In an unrelated development, U.S. and Iraqi troops detained a senior Shi'ite insurgent said to have facilitated the import of explosively formed projectiles into Iraq. The suspect was captured in a raid of Baghdad's Sadr City, said to be the headquarters of the Iranian-sponsored Mahdi Army.

Officials said EFPs, designed by Iran and employed by Hizbullah, have killed more than 170 American and coalition soldiers since 2004. The EFP facilitator was not identified.