Benghazi explosion damages police station (CNN) -- An explosion outside a police station in the eastern Libyan city of Benghazi on Saturday morning caused severe damage to the building, said the state news agency, LANA. No casualties were reported in the early morning attack, which shattered several weeks of relative calm for the city's residents. Over the past year, Benghazi, the birthplace of Libya's 2011 revolution, has been the scene of multiple attacks targeting security forces. Many of the attacks have been blamed on Islamist militants. On Friday evening, armed men attacked the headquarters of a government-affiliated militia in the city of Derna, about 120 miles (200 kilometers) east of Benghazi, killing one of its members, LANA reported. After the attack, a car bomb with more than 50 kilograms of explosives was found and defused, the news agency said. Western intelligence sources believe that Islamist militant groups some with links to al Qaeda are active in and around Derna. Earlier in the week, a car bomb carrying a large amount of explosives detonated outside the French Embassy in Tripoli, injuring two French security guards and a Libyan girl. There has been no claim of responsibility for Tuesday's attack. After the French military intervention in Mali in January, there were fears militants could strike French interests in the region, including Libya, which has been struggling to impose security across the country since the 2011 revolution that ousted Moammar Gadhafi. Libyan officials said an investigation was under way to determine who carried out the attack on the embassy. The bomb also damaged surrounding buildings in a residential part of the capital. A team of French investigators has been in the Libyan capital collecting evidence and investigating the bombing. The French Embassy bombing followed a series of attacks last year that targeted foreign diplomatic missions and the International Committee of the Red Cross in Benghazi. The attacks are believed to have been the work of Islamist extremist groups with ties to al Qaeda. Last September, U.S. Ambassador to Libya Chris Stevens and three other Americans were killed in a militant attack on the U.S. Consulate in Benghazi. After Tuesday's bombing, the first targeting a foreign diplomatic mission in Tripoli, Libyan officials said security would be increased around such facilities. The high level of unease was evident when a bomb threat at a cultural event Friday evening led to its cancellation and the evacuation of the foreign diplomats in attendance. The Libya Movie Awards, an event organized by the European Union, the Italian Cultural Institute and the Libyan nongovernmental organization 1 Libya, was being held at a theater adjacent to the Radisson Blu Hotel in central Tripoli. In a news release on Saturday, organizers said they "regret to announce the decision to postpone the First Edition of the Libya Movie Awards (LMA) in light of yesterday evening's security threat." The statement said the rest of the events scheduled for Saturday and Sunday have been postponed until further notice "while insecurity persists" A management source at the Radisson Blu Hotel told CNN the hotel did not receive any threats and was functioning as normal on Saturday. A security official told the Libyan state news agency that security precautions were taken Friday after a member of the security forces guarding the hotel received a call from an unidentified person saying there was a car bomb in the vicinity. The official said security measures were taken immediately and the report appeared to be "baseless."