Story highlights He is a 29-year-old Somali-born U.S. citizen

He is accused of providing material support to Al Shabaab

(CNN) In under three years Liban Haji Mohamed has gone from driving a cab in Washington, D.C., to a spot on the FBI's Most Wanted Terrorists list.

The bureau on Thursday announced Mohamed's addition to the list as well as a $50,000 reward for any information on the 29-year-old Somali-born U.S. citizen.

The FBI says Mohamed is accused of providing material support to Al Shabaab, the Somali-based group that's linked to al Qaeda. The group has launched many deadly terrorist attacks, including one on a popular mall in Kenya in 2013. The Westgate Mall attack lasted four days and killed dozens.

Mohamed left the United States in the summer of 2012 attempting to join Al Shabaab, the FBI said. Interpol has sought him ever since.

"Not only did he choose to go to Somalia and fight with Al Shabaab, he took a prominent role in trying to recruit people to fight for Al Shabaab," said Carl Ghatas, special agent in charge of the counterterrorism division at the FBI's Washington field office.

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