A Sriwijaya Air flight with 56 passengers and six crew members on board is believed to have crashed shortly after taking off from Indonesian capital Jakarta on Saturday.

"We found body parts, life jackets, avtur (aviation turbine fuel) and debris of the plane," Captain Eko Surya Hadi, commander of Trisula coastguard ship, told local TV.

The Chinese Embassy to Indonesia contacted Indonesian authorities after the crash and confirmed that no Chinese nationals were on board. 

Flight SJY182 was reportedly a 26-year-old Boeing 737-500. 

The plane lost more than 10,000 feet of altitude in less than one minute, about four minutes after departure from Jakarta, according to airspeed and altitude data on FlightRadar24.

The plane took off from the airport at 2:36 p.m. local time (0736 GMT), according to FlightRadar24, and was en route to Pontianak.

The usual flight time is about 90 minutes over the Java Sea between Indonesia's main Java island and Kalimantan, the country's section of Borneo island. 

Sriwijaya Air said it is still gathering detailed information regarding the flight before it can make any statement.

On October 29, 2018, all 189 people aboard were killed after a Boeing 737 Max plane of Indonesia's Lion Air crashed into the Java Sea shortly after taking off from Jakarta.