SINGAPORE - The boatman who is missing after his bumboat caught fire on the Singapore River on Tuesday (July 12) evening had been working for Singapore River Cruise for about a year.

Mr Ong Hock Long, 33, was on his way to pick up passengers at the Esplanade bumboat stop when his boat, number 36, caught fire, said a colleague who did not want to be named.

He was the only person on the battery-operated boat at the time of the fire. He jumped off the back of the boat when it caught fire.

Another boat approached his, and its crew prepared to throw a life buoy, but Mr Ong did not surface, the colleague said.

Mr Ong's family was seen waiting for news of him at the Esplanade outdoor amphitheatre stand on Wednesday afternoon.

The Straits Times understands that each boat has a fire extinguisher, about 30 life vests and four life buoys, and the boat captains can usually swim.

The Singapore Civil Defence Force (SCDF) has called off the underwater search for him.

An SCDF spokesman said on Wednesday morning that a surface search resumed after its underwater search ceased at around midnight.

When The Straits Times arrived at the bank of the Singapore River on Wednesday morning, the charred bumboat was seen moored near the Esplanade.

Several SCDF officers, as well as four women who appeared to be family members of the boatman, were also spotted at the scene.

The fire, which occurred at about 6.30pm on Tuesday, was put out by SCDF using two water jets from the riverbank.

Eyewitness videos posted on social media had shown massive plumes of smoke rising from the boat.

The search for the boatman commenced after the fire was put out, with SCDF deploying its elite Dart divers, who faced challenges such as poor underwater visibility at night and having to submerge and search through the deep silt of the river bed.

Their methods of search included point diving at a depth of about 4m and employing a circular search pattern from the point where the boatman was last seen, with the search team moving in a grid formation.