MOGADISHU -- Several people are feared dead in multiple explosions near Aden Adde Airport in Somalia capital Mogadishu on Sunday, witnesses and security officials said.

A vehicle loaded with explosives belonging to terror group Al-Shabaab exploded after being captured by security forces in Mogadishu near the airport.

Witnesses and security officials said the incident which caused huge explosion sparked off a fierce exchange of gunfire between the security forces and the armed attackers in the restive city.

Some witnesses said three mortar shells landed at residential areas adjacent to the airport and African Union Mission in Somalia (AMISOM)'s Halane military base.

"The security forces are currently engaging the armed attacks in gunfight. A truck with the mortar gun has been seized," said one of the witnesses who declined to be named.