Bangkok, Aug 26 (IANS): As many as 22 people have been killed and 19 others injured in monsoon-induced flash floods and landslides across Thailand that affected over 30,900 households in 13 regions since August 16, authorities said on Monday.

Authorities are ramping up efforts to drain floodwaters brought by heavy monsoon rains and provide relief to the affected 737 villages in five regions of the Southeast Asian country, the Department of Disaster Prevention and Mitigation said in a statement.

The agency also warned residents in 31 regions across the country to be vigilant for flash floods, forest runoffs, and strong winds until Thursday, as officials have been instructed to closely monitor the situation and prepare emergency response teams and machinery to be stationed in the high-risk areas, Xinhua news agency reported.

Severe flooding persists in five northern regions, such as Chiang Rai, Sukhothai, and Prae, while there is a high risk of water levels rising in areas near the Chao Phraya River, including the capital Bangkok, though the levels are still manageable.

While Thailand experiences annual monsoon rain in the last quarter of the year, man-made climate change is causing more intense weather patterns that can make destructive floods more likely.

Widespread flooding across Thailand in 2011 killed more than 500 people and damaged millions of homes around the country.

The flooding began at the end of July triggered by the landfall of Tropical Storm Nock-ten and soon spread through the provinces of northern, northeastern, and central Thailand along the Mekong and Chao Phraya river basins.