MANILA - Philippine officials scampered to send relief aid on Monday to hundreds of thousands hit by weekend floods in and around Manila, while anger mounted over what was seen as an inadequate response from the government.

As the death toll from flash floods soared to 140, analysts said the anger could damage the prospects of Defense Secretary Gilberto Teodoro, the administration's candidate in the May 2010 presidential election.

"His 0.2 percent popularity could be zero by now," said political analyst and columnist Nelson Navarro, of Teodoro.

President Gloria Macapagal Arroyo, already deeply unpopular in opinion polls, ordered an emergency center be set up in the presidential palace on Monday, two days after the floods, highlighting for some the haphazard response to the disaster.

At least 450,000 people were affected, including about 150,000 displaced.

Officials said the economic damage from the worst rains on record in the Manila area was about P1.4 billion ($30 million), including P500 million in lost crops. Damaged roads and bridges accounted for most of the remaining costs.

Officials expected the toll to rise with people looking for missing relatives and residents trapped in flooded houses two days after Typhoon Ketsana dumped about 410 mm of rain in 24 hours, about the average amount of rainfall for an entire month.

'Once-in-a-lifetime typhoon'

Mrs. Arroyo called the typhoon "an extreme event that has strained our response capabilities to the limit. But it is not breaking us." "It's a once-in-a-lifetime typhoon," she said in a statement. "We are continuing the rescue efforts until everyone in danger is accounted for."

While waters had receded from most flooded areas in Manila, some parts of the city of 15 million remained cut off and in others, mud and garbage was left caked on streets.

Schools were ordered closed, but financial markets were open on Monday and public transport was operating. Offices and businesses were open, but attendance was poor.

"There was a massive failure in government and the direction of management response," said Mario Taguiwalo, president of the National Institute for Policy Studies think-tank.

"The root cause is you have a government whose predominant preoccupation is with graft and corruption -- how to steal more money from the people," Taguiwalo said.

"If your officials are not motivated to serve and just motivated to steal, then that's the kind of response you get."

'Too little, too late'

For many the disaster revealed the divisions that separate the city's rich and poor, and problems with planning and development in the city.

"Why is it that rich villages get help first?" said Bobby Santillosa, head of a neighborhood-based disaster-response team in Bagong Silangan, a low-income northern Manila neighbourhood.

The community leader saw 29 neighbors drown in the flooding sparked by tropical storm Ketsana, when more than a month of rain fell in less than nine hours.

"They were already dead when rescuers arrived," he added.

Bayani Fernando, the Metropolitan Manila Development Authority chief who is responsible for flood control in the capital, said that among the major factors in the flood were poor city planning, illegal structures and simple geography.

"Our problem is we live where we should never have lived," he said.

Manila, which like most of the country lies on the Pacific typhoon belt, is bisected by the Pasig and Marikina rivers whose waters connect Manila Bay to the west with a huge lake, Laguna de Bay, to the east.

Some areas of the city lie below sea level, sit on silt and rely on pumps to keep the water out, while the eastern district of Marikina, ground zero of the disaster, is a valley surrounded by the Sierra Madre mountain range.

He said obstructions, either caused by squatters putting up illegal structures or rich landowners encroaching on land such as riverbanks that allow natural drainage, should be removed.

"If we want to stop this, we have to remove all the things that are obstructing the waters," Fernando said. With reports from Reuters and Agence France-Presse