TRIPOLI, Libya (AP) — Human Rights Watch says Libyan prison authorities should investigate the alleged abuse of a son of former dictator Moammar Gadhafi and other inmates in a Tripoli prison. In a statement late Monday, the U.S.-based group said a video made available by news website Clearnews apparently showed guards beating Al-Saadi Gadhafi on the soles of his feet during an interrogation at al-Hadba prison.