By Carly Walsh and Ben Westcott, CNN

(CNN) -- Hundreds of people are missing and thousands more have been displaced after a dam collapsed in southern Laos, causing flash flooding across six villages, according to the state news agency.

The Lao News Agency said the Xepian-Xe Nam Noy hydropower dam collapsed at 8 p.m. on Monday night, triggering the catastrophic release of 5 billion cubic meters of water.

Houses were washed away in the torrent, which caused several deaths and left more than 6,000 people homeless.

Laotian Prime Minister Thongloun Sisoulith suspended a planned monthly government meeting to monitor the rescue and relief efforts, the agency said.

Authorities have made a public appeal for emergency aid for the victims of the flooding, including clothing, food, water and medicine.

Pauline Arce, regional disaster law officer for the International Federation of the Red Cross Asia-Pacific, said the Laos National Disaster Prevention and Control Committee had met to discuss the disaster.

She said the IFRC was preparing to issue emergency relief funds for Laos within the next 24 hours, but was already sending relief kits to help 1,000 people displaced by the floods and is helping with search and rescue operations.

The disaster is so far known to have affected at least six villages in the Sanamxay district of Attapeu province. There is no official information yet about how badly the dam has been damaged, what caused it to break or when the flooding is expected to recede.

US non-governmental organization International Rivers said the break was caused by ongoing heavy monsoon conditions and heavy rain in Laos.

Construction on the dam began in February 2013 and commercial operations were expected to begin in 2018. It was due to cost an estimated $1.02 billion.

The South Korean construction company building the dam, SK Construction Co., has dispatched a rescue crew including helicopters and boats to Laos, South Korea's Ministry of Foreign Affairs said in a statement Tuesday.

According to the ministry, 53 Koreans who were working at the site have been evacuated.