Indonesian authorities are continuing the search for wreckage of a Boeing 737-500 passenger jet carrying 62 people that plunged sharply, then crashed into the sea shortly after taking off in Jakarta on Saturday afternoon.

About 10 navy ships with divers have been deployed to an area of the Thousand Islands in the waters just north-west of the capital, where officials said they believed Sriwijaya Air Flight 182 crashed.

Joko Widodo, Indonesia’s President, on Sunday confirmed the crash and expressed his condolences for what he called the “tragedy”. The Indonesian leader said in a statement that after receiving word the plane had lost radar contact, he had ordered relevant authorities to carry out search and rescue operations.

Indonesia’s national search and rescue agency began the search for wreckage on Saturday evening. It said that it had collected pieces it thought came from the aircraft at the location, but struggled with poor visibility before resuming the search on Sunday.

According to the flight tracking group Flightradar24, the plane lost more than 10,000 feet (3,048 meters) of altitude in less than a minute, about four minutes after it took off in Jakarta on Saturday.

Flight SJ-182 was heading to Pontianak, the capital of Jakarta’s West Kalimantan province on the island of Borneo, when it took off at 2:36pm, then disappeared from radar at about 2:40pm local time.

The aircraft, which was 26 years old, did not send a distress signal, air marshal Bagus Puruhito, the head of Indonesia’s national search and rescue agency told local media.

Fishermen in the area at the time of the crash told the Associated Press they heard an explosion at around 2:30pm.

Police set up a disaster victim identification command post at a police hospital in East Jakarta to identify victims of the crash, Indonesia’s Antara news agency reported on Sunday.

The Boeing plane was a much older model than the 737 MAX involved in Indonesia’s Lion Air crash in 2018 that killed 189 people and the Ethiopian Airlines crash in 2019 that killed 157.

“We are aware of media reports from Jakarta regarding Sriwijaya Air flight SJ-182,” Boeing said in a statement on Saturday. “Our thoughts are with the crew, passengers, and their families. We are in contact with our airline customer and stand ready to support them during this difficult time.”