Jakarta - At least 20 people were killed and many more injured after a dam broke near the Indonesian capital Jakarta Friday, officials said.

The Situ Gintung dam in Tangerang district, just outside the capital Jakarta, collapsed at about 2 am (1900 GMT Thursday), sending water crashing into a crowded residential area, said Rustam Pakaya, the head of the Health Ministry's crisis centre.

Hundreds of homes were submerged and many swept away, he said. "It was like a tsunami," Pakaya said.

Residents said hours of heavy rain on Thursday may have caused the 10-meter-high dam to break.

A resident, Mabruri, told TV One channel that his house and bean curd factory were swept away by the flood.

"Fortunately no one was in the factory but I saw two of my neighbors being swept away," he said.

"Something like this never happened before. There were leaks before but officials just took pictures and didn't do anything about," he told the station.

Pakaya said the death toll could rise and some residents may be missing.

Rescue teams have been dispatched to the area where water was as deep as 2 metres in some places. (dpa)