Witnesses say Syrian security forces have clashed with gunmen thought to be Islamist militants in the northwestern city of Aleppo.

The Associated Press quotes residents as saying the clashes occurred Sunday on a road leading to the airport in the city.

Al Jazeera television said as many as three gunmen died when they blew up their car after being surrounded by police. There were no reports of further casualties.

There has been no official confirmation of the clash from the Damascus government.

Some information for this report provided by AP and Reuters.