MANILA -- Initial search by the Philippine military for the Malaysian aircraft that went missing Saturday morning had been unsuccessful by Sunday afternoon, Philippine military said later that day.

In a phone interview, Lieutenant General Roy Deveraturda, chief of the Western Command (Wescom) of the country's armed forces, said they have completed three sorties of aerial reconnaissance flights since the plane was reported missing.

"There's negative sighting. We are doing another search pattern. We might be launching (another search) again later," he said.

"They saw nothing, so they are going to check areas that were not covered," said Deveraturda of the reconnaissance flights. "We' re doing this because there are no words yet confirming it has been found," he said.

Meanwhile, Wescom spokeswoman Cheryl Tindog said three naval vessels have been sent to search the missing plane, but their efforts have so far failed, too.

Deveraturda said the aerial and naval search is conducted within the country's 200-mile exclusive economic zone (EEZ). He said a search outside the country's EEZ would require clearance from higher authorities.

He said they are conducting the search in case the plane, carrying 239 passengers, veered towards the Philippines. The plane came from Kuala Lumpur and was bound for Beijing.

"While the possibility is very slim, who knows since it has yet to be located, that's why we are participating in the search...We are going to participate in the search until such time that there is already a sighting or confirmation on the location of the aircraft," he said.