At least seven civilians were killed and 18 others wounded in fighting between al-Shabab and government forces backed by the AU troops, police in the capital said.
Civilians bear the brunt of Somalia fighting
The parliament was meeting for the first time since al-Shabab and Hizb al-Islam groups launched an anti-government offensive in May.
“Several mortar shells struck the compound where we were having a session but there were no casualties. The session was called off after the attack and will continue tomorrow,” Mohamed Adan, a legislator said.
Some 300 MPs were meeting in a building in the south of the capital Mogadishu when al-Shabab fighters began firing mortars.
“We heard explosions of mortar as we started our session minutes after the president left the compound,” said Hussein Ali, another MP.