A typhoon that had left the Philippines after killing nearly 600 people and leaving hundreds missing in the south of the country has made a U-turn and is now threatening its northwest, officials said on Saturday.

The weather bureau raised storm warnings over parts of the main northern island of Luzon after Typhoon Bopha veered northeast. There was a strong possibility the disastrous storm would make a second landfall on Sunday, but it might also make a loop and remain in the South China Sea, forecasters said. In either case, it was moving close to shore and disaster officials warned of heavy rains and winds and possible landslides in the mountainous region.

Another calamity in the north would stretch recovery efforts thin. Most government resources, including army and police, are currently focused on the south, where Bopha hit on Tuesday before moving west into the South China Sea.

With many survivors still in shock, soldiers, police and outside volunteers formed most of the teams searching for bodies or signs of life under tons of fallen trees and boulders swept down from steep hills surrounding the worst-hit town of New Bataan, municipal spokesman Marlon Esperanza said.

"We are having a hard time finding guides," he said. "Entire families were killed and the survivors ... appear dazed. They can't move."

He said the rocks, mud, tree trunks and other rubble that litter the town have destroyed landmarks, making it doubly difficult to search places where houses once stood.

On Friday, bodies found jammed under fallen trees that could not be retrieved were marked with makeshift flags made of torn cloth so they could be easily spotted by properly equipped teams.

Authorities decided to bury unidentified bodies in a common grave after forensic officials process them for future identification by relatives, Esperanza said.

The town's damaged public market has been converted into a temporary funeral parlor. A few residents milled around two dozens white wooden coffins, some containing unidentified remains.

One resident, Jing Maniquiz, 37, said she rushed home from Manila for the wake of two of her sisters, but could not bring herself to visit the place where her home once stood in Andap village. Her parents, a brother and nephew are missing.

"I don't want to see it," she said tearfully. "I can't accept that in just an instant I lost my mother, my father, my brother."

She said that at the height of the typhoon, her mother was able to send her a text message saying trees were falling on their house and its roof had been blown away.

Maniquiz said her family sought refuge at a nearby health center, but it was destroyed and they and dozens of others were swept away by the raging waters.

"We are not hopeful that they are still alive. We just want to find their bodies so that we will have closure," she said.

The Associated Press