Officials say Philippine troops attempting to rescue hostages held by the Abu Sayyaf clashed with the militants, leaving two soldiers and five gunmen dead.

Provincial commander Brig. Gen. Cirilito Sobejana says troops encounter around 30 gunmen early Thursday in southern Sulu province. He says soldiers were trying to rescue 23 hostages, including 15 foreigners, amid unconfirmed rumors their captors have threatened to behead some of them.

Sobejana says the militants have separated the hostages among different commanders and it was not clear which captives are being held by the group troops clashed with.

Last month, the military retrieved the decapitated bodies of two Vietnamese crewmen abducted by the Abu Sayyaf last year.