The Philippines has widened a search for the interior minister and two pilots a day since they went missing after a twin-engine light plane carrying them plunged into the sea off the central island of Masbate, the navy commander said on Sunday.
Five navy and coastguard ships, nine aircraft and eight teams of divers searched waters off Masbate for the wreckage of a six-seat Piper Aircraft Seneca plane carrying Interior Minister Jesse Robredo on Saturday.
Security officials said Robredo, 54, was aboard with his bodyguard and two pilots. Only the bodyguard is known to have survived. Fishermen found him floating about 300 metres from the shoreline.
A U.S. military aircraft, equipped with infrared and Sonar, has also joined the search after one navy ship detected some metal on the seabed.
"The process is that if something is detected, it will have to be checked by divers," Vice Admiral Alexander Pama, the navy chief, told reporters in Manila. "There is still no confirmation. We don't want to call it search and recovery."
Pama said there is still hope for a miracle to find the minister alive, but he told Reuters the search area has been widened every hour that passed because of the strong currents in the sea around Masbate.
President Benigno Aquino and his defence minister Voltaire Gazmin, flew to Masbate on Sunday to monitor developments in the search and rescue.
Robredo visited the police training centre in Cebu on Saturday and was returning home to Camarines Sur province when his plane malfunctioned, forcing the pilots to seek the nearest airfield on Masbate.
Witnesses told police they saw the plane crash into the sea, about 500 metres (1,640 feet) from the airport runway.
Robredo is Aquino's close political ally and was presented with a Magsaysay Award, Asia's equivalent of the Nobel prize, in 2000 for reforms introduced as mayor of Naga City in the central Philippines.