Authorities rescued 40 people after the vessel sank in strong winds, meaning it was carrying many more passengers than it was designed for, the coast guard says.

Nguyen Van Son, was convicted of masterminding the theft while head of the coast guard, in what the judge described as a 'particularly serious case' that hurt the image of the defence services, reports say.

The fate of the submersible and those aboard remains a mystery as search teams from the US, Canada and France mount an intensifying search in an area of open sea larger than the state of Connecticut.

The Philippines, an archipelago of more than 7,600 islands, has a poor record for maritime safety, with vessels often overcrowded and many ageing ships still in use.

Reports say the incident took place at the Second Thomas Shoal, when a Chinese coast guard directed the laser at its ship, causing temporary blindness to crew on the bridge and making 'dangerous manoeuvres'.

While the coast guard is still capable of meeting the majority of challenges on the open sea, the time may come when Malaysia should consider beefing up its defence assets.

The spill released some 3,000 barrels of crude oil into the Pacific Ocean, killing wildlife, blackening the coastline and forcing officials to close beaches south of Los Angeles.