Hundreds of thousands of survivors of a deadly Philippines typhoon crammed into overcrowded shelters Friday, braving the stench of corpses as the government vowed action to prevent storm disasters.

Typhoon Bopha, which smashed into the nation's south on Tuesday leaving at least 484 people dead and 383 missing, was the deadliest natural disaster this year in a country that is regularly hit with quakes, floods and volcanic eruptions.

President Benigno Aquino flew into the southern island of Mindanao which bore the brunt of Tuesday's storm, to meet with bruised and grieving survivors who must now rebuild their lives.

"We want to find out why this tragedy happened and how to keep these tragedies from happening again," he told dazed crowds after arriving by helicopter in the town of New Bataan which was mostly obliterated by the storm.

As the president spoke, a yellow excavator tore into the rubble of a row of flattened houses a short distance away, allowing rescue workers to pull out the bodies of two more victims.

Among the 306,000 left homeless by the storm were 2,000 people huddled in a basketball gym in New Bataan, one of only a few buildings left standing in the town which is a centre for the nation's banana and gold mining industries.

With the overpowering stench of decomposing corpses from the parking lot outside, farmer's wife Violy Saging, 38, tried to focus on the needs of her surviving children.

"It (the typhoon) snatched our life away. There is nothing left, but we are hoping our relatives or friends will take us in," she told AFP.

Her eldest son's body was found wrapped around a coconut tree that he had climbed in a vain effort to flee the deluge. The youngest of her three children who survived, a son aged aged three, has a high fever.

The concrete floor of the crowded gym was caked with mud, and part of its roof was blown away by the cyclone, exposing the newly homeless to heavy rain that began pouring again shortly after Aquino left.

Families took turns to sleep on benches around the walls, and the 2,000 occupants had to share the building's two toilet stalls.

The government has appealed for immediate international aid for food, tents, water purification systems and medicine, and warned the homeless face months in evacuation centres before safe places can be found for new homes.

Interior Secretary Mar Roxas told reporters during Aquino's visit that more rescue workers, equipment and canine units, capable of sniffing out any people still alive beneath the rubble, were being fielded in the worst-hit areas.

He said the government is also investigating why so many people were killed even when advance warnings were given ahead of the typhoon.

"They should not have built houses there," Roxas said, noting many of the mining areas which are a magnet for the nation's poor had been declared unsafe for habitation due to frequent deadly landslides.

Outside the gym, Medarda Opiso, 47, joined crowds with handkerchiefs pressed to their noses as they gingerly peeled away death shrouds covering faces and bloated bodies laid out on the pavement.

Her son's wife and daughter are among the missing.

"My son is in despair. He is not talking to anyone. I am afraid he will lose it," Opiso said.

The son, farmer Gomer Opiso, had been tending to his crops when the wall of water and debris nearly wiped out the town of 48,000 people.

But amid the despair there were also some poignant reunions.

Lucrecio Panamogan, 74, found his grown children huddled together with their families in a devastated school yard two days after the storm.

"I thought I had lost them," he told AFP, his tears welling up.

"We may no longer have a house, or any possessions, but we still have each other."