Mogadishu, Somalia (CNN) At least five people have been killed and 10 others injured after a bomb was detonated during a soccer game in Somalia's port city of Barawe, a local official said.

Hundreds of fans were watching the match when Thursday's blast occurred, District Commissioner Hersi Barre told CNN.

Al Qaeda-linked terror group Al-Shabaab later claimed responsibility for the bombing and said it had targeted district and regional officials who were watching the match.

Barawe, a former Al-Shabaab stronghold, lies in Somalia's Lower Shabelle region, about 220 kilometers (137 miles) south of the capital, Mogadishu.

Al-Shabaab has been waging a war with the Somali government for more than 10 years, prompting the African Union to send in peacekeeping troops. The terror group is now based mainly in rural areas in the south of the country, having lost control of Mogadishu in 2011.