Indonesian passenger flight SJ182, which was carrying more than 50 people, is believed to have crashed into the sea shortly after take-off from Jakarta, according to the Indonesian government.

Debris collected from the Java Sea near the last location of the aircraft is believed to be from flight 182 and includes a deflated full size life raft similar to those used in commercial aircrafts.

The 26-year-old Boeing 737-500 aircraft disappeared moments after taking off from Jakarta's Soekarno-Hatta airport.

It was heading north to Pontianak, in Indonesian Borneo.

Indonesia's Minister for Transportation, Mr Budi Karya Sumadi told a press conference that Sriwijaya flight 182 crashed off the coast of Pulau Seribu - a marine national park off the coast of Jakarta.

"On Pulau Seribu, where the plane crashed, objects that are thought to be plane debris have been found but we are still investigating," Mr Sumadi said.

The flight took off from Jakarta at 2.37pm local time.

Sriwijaya has confirmed that 40 adults, seven children, three babies and six crew members members were on board flight 182. That is a total of 56, as opposed to the earlier estimate of 63 people, according to the flight manifest that was acquired by News Corp.

No Australians are believed to have been on the flight.

Mr Sumadi confirmed that Indonesian President Joko Widodo (Jokowi) ordered an immediate investigation into the disappearance of flight 182.

"The plane took off at 14:36 ​​local time and ascended at an altitude of 29,000 feet. At 14:40 the plane was monitored by radar as flying in the wrong direction and within seconds the plane disappeared from the radar. We are concerned for the passengers and crew onboard.

"President Jokowi has ordered a search," Mr Sumadi said.

Radar contact with the aircraft was lost about four minutes after departure and ADS-B flight tracking services showed the aircraft making a rapid descend after reaching an altitude of 3200 metres.

Before disappearing from contact, the aircraft last registered an altitude of just 72 metres, according to Flightradar 24 data - a worldwide real-time flight tracker and mapping app.

Indonesian authorities have launched a search and rescue operation through the KNKT transport authority and the Basarnas rescue agency.

Local Indonesian television footage showed relatives and friends of passengers onboard the budget airline jet weeping, praying and hugging each other as they waited at Jakarta and Pontianak airports, according to AP.

Local media reported that an explosion occurred over the Java Sea and that debris has begun to wash up in Jakarta Bay, though it in not yet confirmed to be from flight SJ182.

Local media reports said fisherman spotted metal objects believed to be parts of the plane in the Thousand Islands archipelago.

"Sriwijaya Air flight #SJ182 lost more than 10.000 feet of altitude in less than one minute, about 4 minutes after departure from Jakarta," Flightradar24 reported.

The Boeing 737-524 flew a short distance north of the airport and above the Java Sea before contact was lost.

Adita Irawati, the Indonesian Transport Ministry spokesman said in a statement to the South Morning China Post: "At this point, we are investigating and co-ordinating the matter with Basarnas (the search and rescue agency) and KNKT (the transport safety body). We will release more information as soon as there are developments."

Boeing has acknowledged the crash in a tweet:

In October 2018, 189 people were killed when a Lion Air Boeing 737 MAX jet crashed into the Java Sea about 12 minutes after take-off from Jakarta on a routine one-hour flight.

That crash, and a subsequent fatal flight in Ethiopia, saw Boeing hit with $2.5 billion in fines over claims it defrauded regulators overseeing the 737 MAX model, which was grounded worldwide following the two deadly crashes.

Originally published as Indonesian plane vanishes after falling 10,000ft