Tripoli, which has been controlled by Islamist militiamen mostly from the western city of Misrata since the summer, has been hit with a series of car bombs and shootings. The internationally recognized government has been forced to relocate to the country's east, where a former general has waged an offensive against Islamist militias, including Ansar al-Shariah, blamed for the 2012 attack on the U.S. diplomatic mission in Benghazi that left the U.S. ambassador and three other Americans dead.