A Philippine Navy helicopter crashed at sea Tuesday while taking photos and videos off the coast of Zamboanga City in Mindanao, officials said. Officials said three passengers were rescued from the Bolkow chopper, but its two pilots were still missing. We have rescued the three passengers and efforts are going on to find the two pilots who are still unaccounted for, said Lieutenant Hari Cunanan, a spokesman for the Philippine Navy in Mindanao. Cunanan said those rescued Petty officers Rodolfo Pataueg, Noel Ridad and Abdon Martinez were taken to a military hospital. They are now in stable condition, he said. He said the chopper was taking aerial photos and videos off Zamboanga City as part of a routine exercise when the aircraft went down. We still dont know what happened, but this will investigated, the spokesman said. Navy divers and patrol boats were sent to the area near Santa Cruz Islands to help search for the pilots, he said.