The Indonesian navy has released footage of divers searching through the wreckage of a passenger plane which crashed into the sea at the weekend as the hunt for its black boxes resumes.

Sriwijaya Air Boeing 737 left Jakarta with 62 people on board, but vanished from the radar on its way to Borneo island on Saturday.

Search teams have already found aircraft parts and human remains.

The plane's black boxes, which have been located, are yet to be recovered.

One official stressed the urgency of the search mission, which resumed on Monday morning, calling it a "24-hour" operation.

"It's going to be an around-the-clock operation," Rasman MS, head of the search and rescue agency's crash operations told reporters.

"There will be no breaks. The sooner we can find the victims, the better."

According to news wire AFP, some 2,600 personnel are currently involved in the search operation along with dozens of boats and helicopters, which are hauling body parts, wreckage and passengers clothing from waters about 23 metres (75ft) deep.

There are also more than 50 ships involved in the search for the wreckage of flight SJ182, along with 13 aircraft.

There appears to be no hope of finding any survivors.

An investigator with Indonesia's National Transportation Safety Committee (KNKT) told news agency Reuters that authorities hoped to find the black boxes on Monday.

He added that it was possible that the plane broke apart when it hit water, based on debris found so far.

"It possibly ruptured when it hit waters because if it had exploded mid-air, the debris would be distributed more widely," said Nurcahyo Utomo.

Investigators are already analysing items which they believe to be a wheel and part of the plane's fuselage. A turbine from one of its engines is also among the debris that has been recovered.

What happened to the aircraft?
The Sriwijaya Air passenger plane departed from Jakarta's main airport at 14:36 local time (07:36 GMT) on Saturday.

Minutes later, at 14:40, the last contact with the plane was recorded, with the call sign SJY182, according to the transport ministry.

The usual flight time to Pontianak, in West Kalimantan province in the west of the island of Borneo, is 90 minutes.

There were thought to be 50 passengers - including seven children and three babies - and 12 crew on board, though the plane has a capacity of 130. Everyone on board was Indonesian, officials say.

The plane is thought to have dropped more than 3,000m (10,000ft) in less than a minute, according to flight tracking website Flightradar24.com.

Witnesses say they saw and heard at least one explosion.

What do we know about the plane?
The missing aircraft is not a 737 Max, the Boeing model that was grounded from March 2019 until last December following two deadly crashes.

According to registration details, the plane was a 26-year-old Boeing 737-500.

It was in good condition, Sriwijaya Air chief executive Jefferson Irwin Jauwena told reporters. Take-off had been delayed for 30 minutes due to heavy rain, he said.

Sriwijaya Air, founded in 2003, is a local budget airline which flies to Indonesian and other South-east Asian destinations.

The plane went missing about 20km (12 miles) north of the capital Jakarta, not far from where another flight crashed in October 2018.

A total of 189 died when an Indonesian Lion Air flight plunged into the sea about 12 minutes after take-off from the city.

That disaster was blamed on a series of failures in the plane's design, but also faults by the airline and the pilots.

It was one of two crashes that led regulators to pull the Boeing 737 Max from service. The model resumed passenger flights in December after a systems overhaul.