Venezuelan President Hugo Chavez called Colombia's president a "pawn" of the US government and compared him to a mafia boss, raising tensions in a dispute that erupted during mediation efforts to free rebel-held hostages. Chavez on Sunday reiterated accusations that President Alvaro Uribe's US-allied government tried to sabotage the release of two hostages last month, saying the captives' accounts of a bombing by the military in the area showed Colombia aimed to "dynamite" the handover. Chavez accused Uribe of being deceitful, calling him a "coward" and a "pawn of the US empire" during his weekly broadcast. "That man doesn't deserve to be president," Chavez said. "Uribe is suitable to be a mafia boss."