Kuala Lumpur  - A self-employed electrician was killed while his sibling and an employee were seriously injured when their illegally modified natural gas vehicle (NGV) exploded, a news report said Sunday.

Mohamad Hilmi Ishak, 25, was believed to have stopped at a local petrol station in the southern state of Malacca to refuel, while his brother, Rosli Ishak, 30, and their worker, Razali Zin, 31, were waiting in vehicle, when the explosion occurred on Friday, the News Straits Times newspaper said.

Investigations revealed that Hilmi had modified a cooking gas cylinder into a natural gas kit for their van and placed the tank beneath the driver's seat, covered by a sheet of canvas.

The explosion, which shattered the entire front portion of the vehicle, was believed to have been caused by a spark from the engine, which was running at that time.

State Chief Minister Mohamad Ali Rustam, who paid the survivors a visit at a local hospital, has urged the authorities to clamp down on those carrying out illegal modifications to their vehicles.

The director of the Road and Transport Department, Solah Mat Hassan, said several similar incidents in the capital Kuala Lumpur have been reported and urged motorist to only patronise the department's accredited workshops to ensure all safety guidelines have been adhered to. (dpa)