Indonesia's president vowed Thursday to have a nationwide tsunami warning system in place by mid-2008, months ahead of schedule, as emergency teams dug bloated corpses from the ruins of houses and hotels along Java island's battered coast.

The death toll from Monday's tsunami stood at 531, officials said, with more than 270 others missing.

"We want to expedite efforts to get infrastructure for the tsunami warning system," President Susilo Bambang Yudhoyono told residents in another coastal area that was rattled Tuesday by a powerful quake.

"I will work with parliament to get the budget."

A magnitude 7.7 earthquake triggered Monday's tsunami, which smashed into a 110-mile stretch of Java's southern coast, destroying scores of houses, restaurants and hotels. Cars, motorbikes and boats were left mangled amid fishing nets, furniture and other debris.

Thousands of frightened locals prepared to spend a fourth night in hillside camps overlooking the sea Thursday, as others did what they could to bring back a sense of normalcy to their shattered lives.

"I am traumatized," said Sri Rahayu, 34, who like many others has refused to return to her home amid fears a series of powerful aftershocks could trigger more walls of water. "I won't go until the government announces formally it is safe," she said.

Police and army teams with dogs and mechanical equipment, meanwhile, continued to hunt for bodies in the debris, while others started going island to island in search of victims who were possibly swept to sea.

In hardest hit Pangandaran, hundreds of people stood at the edge of a mass grave, some covering their mouths as unidentified corpses — photographed and tagged in case relatives later wanted to claim them — were lowered into the ground.

"I hope nothing like this ever happens again ... it's horrifying," said Yeni Sukmayani, 44, who said she came to the ceremony with her 4-year-old twins so they could see for themselves nature's devastating power.

Others scoured the beach for nails, wood, tin — anything they could use to start rebuilding their lives.

"We need a family shelter," said Sakiman, 71, who lives with his family in a makeshift tent camp overlooking the beach. "The camps are crowded, inconvenient. We've received donations of rice and noodles, but can't cook them because the water is too dirty."

The government has come under fire for failing to warn residents about the impending disaster or, in at least one case, misinforming the public about the sequence of events in its aftermath.

Vice President Jusuf Kalla claimed most people fled inland after the earthquake, so "in actual fact there was a kind of natural early warning system."

But almost all people interviewed by The Associated Press said they did not feel the earthquake that struck deep beneath the Indian Ocean, some 150 miles southwest of Java's coast.

Rahayu, who escaped with her 5-year-old daughter, said she would not have known what was happening if her teenage neighbor hadn't run out in panic screaming, "The water is rising! Run!"

In addition to the lives lost, Monday's tsunami left thousands of people who worked in shops, bars, hotels or as tour guides wondering if tourists would ever come back. The industry was already struggling because of several terrorist attacks to hit the nation — especially the 2002 Bali bombings that killed 202 people.

Lilianti Bachtiar, who runs the Grand Mutiara Hotel with her American husband, Oscar, saved her grandchildren by grabbing them from their rooms and running to the second floor when she heard neighbors screaming.

"The waves broke down the walls and washed away the car. We don't have a business anymore. It will be at least a year before we have recovered," she said from a run-down motel in Banjar, a nearby city.

Her family all survived, but she identified the body of a former employee at a temporary morgue.

Indonesia was hardest-hit by a 2004 tsunami that killed at least 216,000 people in a dozen Indian Ocean nations — with more than half the deaths occurring in Aceh province on Sumatra island.

The government began the monumental task of installing an early alert system after that disaster, deploying monitoring buoys off Sumatra island, but it still needs to be extended to Java and thousands of other islands across the sprawling archipelago.

Yudhoyono said the original plan called for the creation of a nationwide network by 2009, but he promised to do what he could to push forward the date by several months.