The FBI said Thursday one of the bombers has been identified as Farah Mohamed Beledi. Authorities believe the 27-year-old left Minnesota in October 2009 for Somalia.
The FBI used fingerprints to confirm Beledi's identity. Investigators are still trying to identify the other suicide bomber.
The May 30 attack at a government checkpoint in Mogadishu killed two African Union troops and one government soldier. Authorities in Mogadishu said it began with a firefight, in which one suicide bomber was shot before his explosive detonated.
Beledi had faced terror-related charges in Minnesota. Since September 2007, more than 20 men have left Minnesota to possibly take up arms with the terror group al-Shabab.