A Malaysian bus bound for Singapore was hit by armed thieves posing as passengers who put a gun to the driver's head and robbed those on board of cash and valuables, reports said today.

The robbery, which took place in the early hours yesterday, netted jewellery, cash and cell phones worth some RM12,000 (US$3,300).

District police chief Jalil Talib said none of the passengers, who included eight Indonesians, or the two drivers on board the bus were harmed in the attack, which was the second of its kind in recent years.

Passengers were sleeping

"The passengers were in a state of shock and simply complied with the robbers' demands," he said, according to the New Straits Times .

The robbers struck as most of the passengers were sleeping. The ringleader put a gun to the driver's head while his accomplices woke the passengers and forced them to hand over their belongings.

Police said they then pulled into an emergency lane and fled in a waiting getaway vehicle that had tailed the bus from its departure in the northern resort island of Penang.