More than 100 people have been killed in a series of landslides brought about by heavy rain in mountainous provinces of the northern Philippines.

Seventy-five people were confirmed dead with 36 still missing in Benguet province as landslides struck in five towns, said provincial police chief, Superintendent Loreto Espinili.

Officials said the death toll would likely rise.

"Our estimate is that more than 100 people were buried," warned provincial civil defence chief Olive Luces.

"The damage in the region is massive. We have several reports of landslides across the region, especially in Benguet. Bodies are being recovered," she said.

In the mountain resort city of Baguio, 17 people were killed as landslides buried whole houses in different parts of the city, said city administrator and civil defence official Peter Fianza.

A landslide also left five dead and 32 missing in Mountain Province, said provincial governor Maximo Dalog.

The northern Philippines has been pounded by heavy rain since Typhoon Parma hit the country on Saturday.

Parma weakened into a tropical depression but has lingered over the north of the Philippines' main island of Luzon.

The National Disaster Coordinating Council's death toll from Parma on Friday morning was 25, however council administrator Glen Rabonza said the latest fatalities from landslides in the north were not yet included in that tally.

Parma hit the Philippines exactly one week after tropical storm Ketsana pounded Manila to the south on Luzon, killing at least 337 people.