At least nine people have been killed and almost 20,000 people evacuated after flash flooding submerged parts of Indonesia's capital and nearby towns.

Key points:

• Almost 20,000 displaced residents in Jakarta have been evacuated to temporary shelters
• Rising rivers have submerged up to 90 neighbourhoods, according to officials
• One man reportedly died of hypothermia, while a 16-year-old boy was electrocuted

Heavy monsoonal rains since New Year's Eve have inundated areas of the capital, filling homes and streets and washing away cars.

In Jakarta's east, many houses were submerged up to their roofs, with the water level reaching as high as 2 metres in parts.

"As of 4:00pm [Wednesday], there are 19,079 displaced residents who have been evacuated at temporary shelters throughout Jakarta," city governor Anies Baswedan said in a news conference.

"The rain in Jakarta has stopped, now we are waiting for the water to recede."

Water levels in east and south Jakarta as well as in the satellite cities of Tangerang and Bekasi in West Java province started to quickly rise from 3:00 am (local time), according to the Disaster Mitigation Agency, who also said monsoonal rains and rising rivers have submerged up to 90 neighbourhoods.

Indonesia's state electricity utility said it had switched off the electricity in hundreds of districts in Jakarta, which is home to 30 million people.

The company said in a press statement that 724 flood-hit areas of the city had been shut down to prevent any electricity-related accidents.