More than 300 people have been in killed by a powerful typhoon in the Philippines that destroyed homes, flooded towns, severed power and communications lines and displaced hundreds of thousands in its central and southern regions.

Military airplanes and naval vessels were dispatched to carry aid to areas devastated by Typhoon Rai, as the country grappled with the strongest of 15 such storms to hit the archipelago this year.

"We are still assessing the damage, but it is huge," Defence Secretary Delfin Lorenzana told reporters. "The first thing we are doing is address the food and water (supplies) and medical care of the injured."

Secretary Lorenzana told the armed forces to deliver relief goods using all available assets, and send in more troops if necessary.

The number of storm-related deaths climbed throughout the day as rescue efforts continued in hard-hit areas.

As of 1000GMT, the death toll from Rai had risen to 375, the police said in a report, making it one of the deadliest typhoons to have struck the Southeast Asian nation.

The number of injured has climbed to 500, while 56 people were missing.

Residents gather their belongings on the side of a road after their houses on Siargao Island were destroyed

The count, which according to the police was subject to validation, far outstripped the 58 deaths recorded by the national disaster agency, which said it was still checking reports from affected areas.

The majority of the deaths reported by police were in the central region of Visayas, home to dive spots in Bohol province, among some of the most popular tourist destinations, and the Caraga region in northeastern Mindanao.

Provincial governor Arthur Yap told broadcaster CNN Philippines he feared the death toll could rise further, as a lack of mobile telephone links made it hard to gather information.

Residents stand next to a destroyed market building in General Luna town, Siargao island