Suspicion that a Norwegian was involved `` has been strengthened , '' security service says . The Al-Shabaab citizen in question has not been named by authorities . Norway 's security service is investigating in Norway and Kenya . The suspect is believed to have ties to a top Norwegian commander , known as Mohamed Abdikadir Mohamed .
Suspicion that a Norwegian was involved `` has been strengthened , '' security service says . The Norwegian citizen in question has not been named by authorities . Norway 's security service is investigating in Kenya and Norway . The suspect is believed to have ties to a top Al-Shabaab commander , known as Ikrima .