The Philippine president, Benigno Aquino, has visited the southern island of Mindanao which bore the brunt of Typhoon Bopha to meet survivors who must now rebuild their lives.

In a surprising development on Friday, Bopha regained strength and threatened to bring flooding into parts of northern Luzon over the weekend.

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

Bopha, which smashed into the nation's south on Tuesday leaving at least 420 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.

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

With Bopha leaving approximately 306,000 people homeless, the Philippine government has appealed for immediate international aid for food, tents, water purification systems and medicine.

It has also said that the homeless face months in evacuation centres before safe places can be found for new homes.

Storm regains strength

"The winds are back up to 150 gusting 185kph. They are expected to increase to 170 gusting 200kph around 6:00am on Saturday. That makes it the equivalent of a Cat 2," Everton Fox, Al Jazeera's broadcast meteorologist, said.

"Satellites show goods signs of the storm reorganising with a clearly marked eye now visible.

"The storm is currently expected to stay to the west of Luzon but will bring showers or longer spells of rain across the north and more especially the northeast. It is moving very slowly and erratically at only 13kph so some areas will have heavy rain for longer.

"Some parts could see 100 to 150mm over the next couple of days. The good news is that this part of the country is more capable of handling such conditions."

Investigations ordered

Mar Roxas, interior secretary, announced during Aquino's visit to Mindanao 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 was also investigating why so many people were killed even when advance warnings were given in advance 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.

Al Jazeera's Marga Ortigas, reporting from Compstela Valley, said that Bopha had left most people fearing the slightest drops of rain.

"Any little shower has them really seeking shelter, worried that the storm might come back," she said.

She said that rescue operations are "ill-equipped" and "undermanned".

"You've got the military and the police, as well as civilians actually helping out," she said.

"There are still places that they haven't got to to that they are trying to get to despite the current weather conditions.

Source: Al Jazeera And Agencies