Ali Moussa Daqdouq, a Lebanese militant accused of involvement in the murder of several U.S. soldiers in Iraq, was released by Iraqi authorities Friday morning, Daqdouq's lawyer, Abdulalmehdi al-Mutairi,said.
Daqdouq has arrived in Lebanon, his lawyer said.
"Thank God, he arrived in Lebanon a few hours ago after he left Iraq this afternoon" al-Mutairi told CNN. "There is no legal reason for his detention. He should have been released months ago".
An Iraqi court cleared Daqdouq in May, saying there wasn't enough evidence against him, an official with Iraq's judicial council told CNN.
The automatic appeal following that ruling affirmed the acquittal in June, according to al-Mutairi.
U.S. officials say Daqdouq organized a kidnapping in the Iraqi city of Karbala in January 2007 that left five U.S. soldiers dead.
Officials said he was a 24-year veteran of Hezbollah who had commanded a special operations group sent to Iraq to develop "special groups" within Shiite militia. U.S. forces captured him in 2007.
Daqdouq had been held in U.S. custody as an "enemy combatant" until the United States ended its military mission in December and handed him over to Iraqi authorities.
"This is an outrage," said Senator John McCain, R-Arizona. "The families of those who were killed by this terrorist should also be outraged and appropriate action should be taken as regards to our relations with the Iraqi government.
The State Department said it expressed its "deep dissatisfaction" with the Iraqi government's decision to release Daqdouq.
"We continue to believe that Daqdouq should be held accountable for his crimes. We've made this point very clearly to the government of Iraq," said State Department spokeswoman Victoria Nuland. "While we strongly object to his release, we've been informed by the Iraqis that they determined that they were no longer able to hold him under Iraqi law."
The State Department has made contact with the Lebanese government on this issue, according to Nuland, and will continue to pursue all "legal means" to bring Daqdouq to justice.