Unknown gunmen have reportedly shot dead a Libyan army general in the eastern city of Benghazi, the latest of a string of deadly attacks on security officials there since a popular revolt ousted the late leader Muammar Gaddafi.

Mohammed Hadia, who was also a high-ranking defence ministry official, was leaving a mosque after Friday prayers when he was ambushed.

"My father was returning from the mosque after Friday prayers with a neighbour when a car stopped in front of them with four people on board," Ahmad Hadia, one of the victim's sons said.

"They asked for his identity, then shot him dead," he added.

The motive for the murder was not immediately clear. 

Hadia was one of the first officers to defect and join the opposition during last year's revolution that ousted Gaddafi. After the revolution he was appointed head of armaments at the defence ministry.

Hadia is the latest of dozens of security officials murdered in Benghazi, especially of officers who had served under Gaddafi.

A strong explosion rocked the Libyan military intelligence in Benghazi last week but caused no casualties. 

Last Sunday, Suleiman Bouzrida, a former military intelligence colonel, was shot in the head twice while walking to a mosque for early morning prayers. He also had joined the rebels in the early stages of the revolution.