A gang of thieves have stolen computer chips reportedly worth millions of US dollars in a raid on an air cargo terminal in Batu Muang, Malaysia.

"The incident occurred between 2.00am and 3.30am [on Monday] when the group, with weapons, forced its way into the [Penang International Airport Free Commercial Zone] facility after overpowering the personnel on duty at the Malaysia Airlines security checkpoint and the Royal Malaysian Customs office," MASkargo (Malaysia Airlines Cargo) said in a statement.

Malaysian police are investigating the theft, MASkargo said.

The gang of 20 thieves subdued 17 security guards using weapons and chloroform before stealing 585 cartons and 18 pallets of microchips and motherboards manufactured by a multinational company in Bayan Lepas, Malaysia, The Star newspaper reported. The stolen goods were estimated to be worth $12.7m (£6.7m), making the theft the largest ever in Malaysia, it said.

News reports in Malaysia have not named the multinational company that produced the chips. Several large companies, including Dell, Intel and AMD, have operations in Bayan Lepas.