The financial cost of Thailand's worst flooding in 50 years is growing, as waters have submerged many industrial centers, halting production and forcing workers and residents to flee.

The floods caused by heavy rains since July have killed about 310 people in Thailand so far. Floods are expected to cut economic growth by about 1.5 percent this year.

Critics have said the government's flood control measures have failed, and that erratic information about the flooding has caused confusion.

Soldiers and government workers piled more than 1 million sandbags onto weakening flood walls protecting northern Bangkok Tuesday. Officials earlier said the flood walls were secure.

China sent a team of experts to Thailand Tuesday to assess the situation and help with flood relief. The official Xinhua news agency quoted the head of the team as saying the worst threat for Bangkok has passed, but that a serious flood threat to the city remains.

More rain is predicted.

United Nations officials say the death toll had risen on Tuesday to more than 700 in Thailand, Laos, Vietnam, Cambodia and the Philippines since torrential rains and tropical storms began hammering the region in late July. A U.N. statement said 8.3 million people have been affected by what forecasters are calling the worst flooding in half a century.

Cambodian officials say their economy also will suffer, with growth expected to be reduced this year by 6 to 7 percent.