A suicide bomber driving a car packed with explosives killed at least five people in Arbil -- the capital of Iraq's Kurdistan region.br br Authorities say the assailant detonated himself as he tried to enter the governor's compound -- protected by blast walls -- in the center of Arbil.br br It's the first major attack in Arbil in more than a year.br br No one has yet to claim responsibility, but Islamic State militants have repeatedly threatened to launch attacks against Iraqi Kurds, who are fighting them along a front line.