Thailand's Prime Minister Yingluck Shinawattra called the flood, which has been ravaging the country's north for more than two months, as the worst in decades in a televised address Friday night.

Buddhist monks wade through floodwater on a street at Chai Wattanaram Temple in Ayutthaya yesterday. At least 252 people have died in flooding in Thailand since mid-July, and water has inundated the 400-year-old temple in the ancient city of Ayutthaya, a World Heritage Site.?[Shanghai Daily]

The flood has killed 252 people and affected more than 2,696, 521 people in 28 provinces according to the Friday update of the Disaster Prevention and Mitigation Department.

Just a month ago, the death toll was barely more than 100, indicating how the flood has worsened recently.

In addition, concerns over public health are growing despite government efforts to send medical supplies to flooded regions, where hospitals are inundated while large groups of homeless evacuees suffer from poor hygienic conditions and polluted water.

About 513,860 people are suffering from flood related disease. And the number of new cases has been increasing at the rate of 20, 000 per day, according to a report from Thailand's Public Health Ministry Friday.

Thousands of people are also having mental disorders. About 3, 104 were under stress and 4,435 people were suffering from depression. About 574 people were having risks of committing suicide, the report added.

Health officials were urged to monitor the outbreak of flood related diseases in the lower northern region and central region.

In the televised speech, Yingluck also warned that flood is threatening the capital city of Bangkok. Flood water is flowing into the city and the government is bracing up for another chunk of water. Meanwhile, a depression is forecasted to pass through Thailand, bringing more rainfalls.

"We need to swiftly discharge water, especially from the Chao Phraya River, as provinces under the dams are facing serious risk, " Yingluck said. The river also runs through Bangkok.

Yingluck said the government has mobilized all its boats to assist victims and is seeking help from the private sector. This is her second speech on the flood in two days. She said the flood has reached a crisis level on Thursday.

About 8,000 troops were sent to help people affected by floods, Thailand's Defence Minister Gen Yuthasak Sasiprapha said Friday.