At least 23 people were confirmed dead on Thursday and thousands were forced to evacuate, after severe flooding hit Indonesia's capital as residents were celebrating the New Year.

Tens of thousands of revellers in Jakarta were soaked by torrential rains as they waited for New Year's eve fireworks on Wednesday.

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Jakarta's domestic airport was also shut, where almost 20,000 passengers were stranded.

National Disaster Mitigation Agency spokesman Agus Wibowo said on Wednesday that monsoon rains and rising rivers submerged at least 90 neighbourhoods and triggered a landslide in Kota Depok, a city on the outskirts of Jakarta.

Wibowo said the dead included a 16-year-old high school student who was electrocuted while more than 19,000 people were in temporary shelters after floodwaters reached up to three metres (10 feet) in several places.

Al-Latif Ilyas Darmawan, the father of the victim, said the rescuers could not save his son, Arviqo Alif Ardana.

"I did not know what had happened until his younger brother came and told me that his brother had died and when I came to the scene, people said that my child was electrocuted when he was holding a lamp post and tried to be rescued by local residents (but failed and died)."

Indonesia's disaster mitigation agency, BNPB, said that at least 16 people were killed including eight in the capital, Jakarta, and three in Kota Depok.

The country's social affairs ministry, however, said that the death toll has already gone up to 21, adding that most of the deaths were recorded in Bogor.

Two more deaths were later reported in the Lebak regency at the south end of Java island.

07.45 Selamat pagi Jakarta, mohon maaf kepada masyarakat atas ketidaknyamanannya atas kondisi pelayanan samsat Jakbar saat ini. pic.twitter.com/sZsKN7370M — TMC Polda Metro Jaya (@TMCPoldaMetro) January 2, 2020

More flooding ahead

Jakarta governor Anies Baswedan told reporters after conducting an aerial survey over the flooded city that as much as 370 millimetres (14.5 inches) of rainfall - more than three times the average amount - was recorded in Jakarta and West Java's hilly areas during the New Year's eve, resulting in the Ciliwung and Cisadane rivers overflowing.

He said about 120,000 rescuers had been deployed to evacuate those affected and install mobile water pumps as more downpours were forecast in coming days.

Authorities warned flooding was possible until April when the rainy season ends.

He said his city administration would complete projects on the two rivers, including a dam and a sluice, to prevent flooding.

Jakarta is home to 10 million people or 30 million including those in its greater metropolitan area. [Dasril Roszandi/AFP]

Television footage and photos released by the agency showed dozens of cars floating in muddy waters while soldiers and rescuers in rubber boats were struggling to evacuate children and the elderly who were holding out on the roofs of their squalid houses.

The floods inundated thousands of homes and buildings in poor and wealthy districts alike, forcing authorities to cut off electricity and water supplies and paralysing transport networks, Wibowo said.

Director General of Civil Aviation Polana Pramesti said the floods also submerged the runway at Jakarta's Halim Perdana Kusumah domestic airport, prompting authorities to close it. About 19,000 passengers are stranded there.

Flooding also highlighted Indonesia's infrastructure problems as it tries to attract foreign investment.

Jakarta is home to 10 million people or 30 million including those in its greater metropolitan area.

It is prone to earthquakes and flooding and is rapidly sinking due to uncontrolled extraction of ground water. Congestion is also estimated to cost the economy $6.5bn a year.

President Joko Widodo announced in August that the capital would move to a site in sparsely populated East Kalimantan province on Borneo island, known for rainforests and orangutans.