Two Libyan army officers have been killed in the past 48 hours in the eastern city of Benghazi, cradle of the 2011 revolt against Moamer Kadhafi, officials and medics said.

The restive east has seen frequent attacks on security forces as the weak government in Tripoli has struggled to exert control over former rebels who have refused to disarm or join the security forces.

A security source said Lieutenant Colonel Mohammed al-Zouei, 39, was killed in a drive-by shooting as he headed to a mosque for Friday prayers. A spokesman for Al-Jala hospital confirmed receiving the body.

Another officer, Lieutenant Colonel Ahmed Soueiri, was shot dead on Thursday, the security source said.

In the two years since Kadhafi was overthrown and killed by rebels Benghazi has seen scores of attacks targeting security forces and foreign missions, including a September 2012 assault on the US consulate that killed the ambassador and three other Americans.

The government has struggled to consolidate control in the vast and mostly desert country, which is effectively ruled by a patchwork of local militias and awash in heavy weapons looted from Kadhafi's arsenals.