Philippine Interior Secretary Jesse Robredo is among three people missing after a small plane crashed at sea off a central island on Saturday, officials said.
The Cessna crashed near the shore of Masbate island while trying to make an emergency landing after suffering an unspecified engine problem, regional military spokesman Colonel Generoso Bolina told reporters.
"Secretary Robredo was in a light aircraft en route to Naga from Cebu. There was an engine problem so they sought permission to make an emergency landing at Masbate, but the plane did not make it there and crashed," Bolina said.
Four people were on the private plane.
Robredo's aide was rescued but the 54-year-old cabinet member and the two pilots remain missing, according to Bolina.
Transport Secretary Manuel Roxas said President Benigno Aquino had been informed of the accident and was keeping track of the search.
"Let us all pray for his safety," Roxas said over Manila's Radio Inquirer.
Roxas said the crash occurred at 4:30 pm (0830 GMT) about one kilometre (0.6 miles) off shore.
The rescuers temporarily called off the search about three hours later as night fell, said their leader Superintendent Gonzalo Villamor.
"There's some undercurrent and by the time it got dark we had not managed to find the aircraft," Villamor told Manila radio station DZBB.
"The aide-de-camp managed to remove his seatbelt and extricate himself just before impact, but he did not see the others," Villamor said. The search would resume at first light, he added.