AdvertisementWhat Does It Mean If An Attack Is 'ISIS-Inspired'?January 22, 2016Dina Temple-RastonfacebookEmailInvestigators prepare to enter one of the residences where suspect Edward Archer lived in Yeadon, Pa. Archer is accused of ambushing a police officer in Philadelphia on Jan. 7. The FBI has said it is investigating the attack as a possible act of terrorism — inspired by ISIS. (AP)