Malaysian Maritime Enforcement Agency (MMEA) said the ROVs would help rescuers locate Lucas Bondezan, 24, who is believed to be in the waters off the northwest tip of Penang Island.

MMEA District II Director Rozali Mohd Said said it was too dangerous for divers to go further into the deep sea as rough seas could threaten rescue efforts.

He added the search had now been expanded from the earlier 10 nautical miles to 15 nautical miles off Muka Head.

“We have decided to use ROVs as it can monitor movements close to the seabed at about 300 metres.

“The ROVs allow us to go beyond the 45 metres below sea level, where the wreckage was found.

“Two extra boats were also deployed for the mission,” he said in a press conference today.

The footage from the ROVs will be channelled to MMEA teams on water to aid rescue efforts.

In the Friday morning mishap, the yacht with four people was on its way from Langkawi, Kedah, to Singapore. They had left at 7pm the night before.

The other three crew members, Novak Novakovic, 28, from Siberia; Rudolf Kolic, 61, (Croatian) and Jaroslav Horejsek, 37 (Czech), were injured in the explosion.

Local fishermen, who were in the vicinity, took the victims to the Alor Star Hospital, with Horejsek transferred to Langkawi Hospital for surgery on his broken leg.

The other two men have been discharged with minor injuries.

MMEA said a fire could have broken out from the engine compartment, which led to the explosion.