Witnesses say Somali insurgents fired mortar shells at the Mogadishu airport Friday during a clash that killed at least seven people.  

They say insurgents began firing after an African Union military plane landed and African Union forces fired shells back. The aircraft was carrying supplies for AU peacekeepers.

Residents report at least one house was destroyed in the fighting.

The AU plane landed at the airport in defiance of a three-day insurgent "ban" on the facility.

Earlier this week, the militant group al-Shabab warned it would attack any plane landing or taking off from the Mogadishu airport after midnight on Tuesday.  

The group says the airport generates money for the Somali government's Ethiopian backers, and is being used by American and Israeli spies.

Aviation officials say commercial airlines stopped using the airport, and it was effectively shut down on Wednesday.

But Somalia's civil aviation authority told airlines that if they do not maintain their normal schedules, they will lose their licenses.

The Elman Human Rights Organization says fighting in Somalia has killed nearly 9,500 Somalis since the start of the Islamist insurgency early last year. The group says that number includes 838 civilians killed since June.  

The insurgents are seeking to drive out Ethiopian troops and topple the western-backed interim government.

Some information for this report was provided by AFP and Reuters.