BENGHAZI, Libya: Bomb attacks targeted two police stations in the eastern Libyan city of Benghazi on Friday, causing extensive material damage but no casualties, a security official said.

“Unknown individuals threw explosive devices at the police stations in Ras Obeida and Al-Madina,” the official told AFP.

The attacks damaged the police stations and several cars parked nearby, he said.

Benghazi, Libya's second city and cradle of the 2011 uprising that toppled the regime of now slain dictator Moamer Kadhafi, is the scene of frequent attacks and assassinations targeting security officials.

Authorities blame radical Islamists for the violence, including a deadly attack in September against the US consulate in Benghazi that killed Ambassador Chris Stevens and four other Americans.

On Thursday, the US State Department issued a travel warning, saying it “strongly advises against all but essential travel to Tripoli and all travel to Benghazi, Bani Walid and southern Libya, including border areas and the regions of Sabha and Kufra.”And on Friday, Britain announced it was temporarily withdrawing some staff from its embassy in Tripoli due to security concerns over recent political unrest.

US authorities took a similar step on Wednesday, saying the security situation in Tripoli had deteriorated as a result of armed groups seizing government buildings in a dispute over a law that would ban officials of the regime of ousted dictator Moamer Kadhafi.