By Andrew Gray
But U.S. Army Lt. Gen. Lloyd Austin, the No. 2 U.S. commander in Iraq, said those leaders would find it more difficult to be successful due to security improvements in their former strongholds.
The U.S. military has accused Iran of arming, training and funding extremist Shi'ite groups in Iraq. Iran denies it is fomenting violence in Iraq and says instability there is caused by the presence of U.S. troops.
The leaders of so-called special groups of militia fighters fled after assaults on their strongholds, such as Sadr City in Baghdad and the southern city of Basra, by U.S. and Iraqi forces in recent months, Austin said.
"We think they went into … Iran for additional training and to be resourced. And we expect that those leaders will try to come back at some point in time in the future," Austin told reporters at the Pentagon by videolink from Iraq.
"Even though we anticipate that some of these leaders will attempt to return soon, we know that they will be returning to a much less permissive environment," he said.
Violence in Iraq has subsided to four-year lows, officials say, thanks to factors including new tactics by U.S. troops, a cease-fire by radical Shi'ite leader Moqtada al-Sadr and a decision by Sunni former insurgents to fight al Qaeda militants.
Austin said Shi'ite extremist groups would have a much harder time winning popular support if their leaders returned.
"Over the last several months, the people have been able to enjoy a much more peaceful environment. I think the people appreciate that," Austin said.
"And so the types of activities that these leaders bring to the neighbourhoods and the provinces, I don't think will be as welcomed as they were in the past," he said.
The United States accuses Iran of providing rockets, armour-piercing bombs and other weapons to Iraqi militants. Austin said fewer such weapons were now making their way into Baghdad.
"In the last several months, we've seen a much decreased flow of those types of weapons, in part because we've been very successful in finding a number of caches that had large stores of those types of munitions and weapons," he said.
"We've taken those off the battlefield. And we've also taken … a number of people who were using those weapons off the battlefield," he said.
(Editing by Mohammad Zargham)
