Somali National Intelligence and Security Agency said its forces arrested Al-Shabab operative following a security operation in the Somali capital Mogadishu.
In a Twitter post, the agency said the suspect was Al-Shabaab bomb expert.
According to the agency, the suspected man was plotting a bomb attack on civilian targets in the capital.
The agency said no civilian was killed or injured during the seizure of the suspected Al Shabaab explosive expert.
The move comes amid Somali military backed by AMISOM forces intensified operations against Al-Shabaab fighters in Southern Somalia.
Al-Shabaab controls several towns and villages in the south and central of Somalia.