Libya’s new prime minister said he would strive to improve security by boosting the national police force and army as well as collecting weapons after a deadly attack on the U.S. consulate in the east.In an interview with Reuters, Mustafa Abu Shagour, voted chief of the next interim government late on Wednesday by the new ruling congress, said he would crack down on militias who have refused to lay down their arms and at times take the law into their own hands."We are going to work very vigorously in building our police force, our army and we are going to allow our young people, especially the revolutionaries   an opportunity to become official members of our security forces,” he said, referring to former rebel fighters."We have to deal with these militias because some of them have nothing to do with the revolution, and are made up of a bunch of criminals. We have to dismantle them.”Militias spearheaded the rebellion that ended Muammar Gaddafi’s rule. While many have scaled back their activities, gone back to their hometowns or merged into national security services, others have yet to give up their arms.The lack of an effective national police force and army mean many of the militias have more power on the ground than Libya’s official rulers.Tuesday’s deadly attack on the U.S. consulate in Benghazi, in which the U.S. ambassador and three embassy staff were killed, has further highlighted Libya’s security failings."We are going to have a vigorous programme to get the weapons back into the hands of the country,” Abu Shagour said.