MOGADISHU, Somalia — A Somali police officer said a suicide bomber detonated an explosives-laden car at a police station in the capital and killed at least five people.Officer Mohamed Abdi said it was a powerful explosion that ripped its victims apart.No group claimed responsibility but the blame usually falls on Islamist insurgent groups who use suicide bombers and explosions as means to defeat a fragile government supported by 8,000 African peacekeepers.Somalia's capital, Mogadishu, has been the epicenter of the country's two decades of violence.