A radical Muslim imam linked to the rampage at Fort Hood is believed to be alive, after it was thought he was killed in an airstrike in Yemen earlier this week.

A source tells Fox News that the FBI now thinks that radical cleric Anwar Awlaki is still alive.

Awlaki was believed to have been killed in a Yemen airstrike that was also thought to have taken out the region's top Al Qaeda leader and 30 other militants.

The raid in Yemen's east targeted an Al Qaeda leadership meeting held to organize terror attacks. U.S. officials believe radical cleric Anwar Awlaki was "probably" one of dozens of militants killed in the strike, a source confirmed to FOX News.