Passengers of a SilkAir flight, including Singaporeans, were stranded at Penang International Airport for about nine hours, as heavy rain and strong wind grounded flights in the Malaysian state.

MI351 was scheduled to depart at around 6pm last Saturday but was repeatedly delayed and eventually cancelled at around midnight, said one of its passengers, Mr Felix Chen, 30.

A replacement flight, MI9351, eventually took off at about 3am yesterday, arriving at Changi Airport Terminal 2 at about 4.30am.

Mr Chen, an advertising account manager who was in Penang for work, said that passengers were stranded at the airport because the roads were flooded.

The overnight storm started around 2pm on Saturday, reports said. It lasted more than 18 hours till yesterday morning, with flood waters rising up to 4m in places. Military and police forces have been deployed to assist victims.

Mr Chen, who was on his way to the airport when it started to rain, said the flood waters on the roads were above ankle height and visibility was very poor because of the deluge. "The jam was quite bad. The driver had to drive very cautiously."

He said passengers stranded at the airport were given regular updates on the situation by SilkAir ground staff, who also provided them with burgers, sandwiches, coffee and water.