Yemeni and U.S. authorities believe Anwar al-Awlaki, a radical al-Qaida-linked cleric, played a role in a number of terrorist attacks. Here is a look at the major incidents.
September 2001: U.S. authorities conduct a series of interviews with Awlaki in the aftermath of the September 11th U.S. terror attacks for his alleged dealings with suspects linked to the plot. However, no criminal charges were filed against him.
August 2006: Awlaki is among a group of five suspects arrested in Yemen for the suspected kidnapping of a Shi'ite Muslim teenager who was held for ransom.