Malaysian police seized 20 kilograms of opium slabs worth some 70,000 ringgit (20,588 dollars) from a suspected dealer in the northern Penang state, a news report said Saturday.
Police surrounded the car of the suspect, aged in his 30s, and discovered 20 slabs of opium after searching the vehicle, said state police chief Salleh Mat Rasid, the dpa reported.
"We planned for four days before deciding to act against the suspect," Salleh was quoted as saying by the Star daily.
The suspected trafficker was believed to be waiting for a potential buyer during the time of the arrest.
Police said the man has been placed under remand for questioning before he is charged with drug possession and trafficking.
Malaysia's tough drug laws impose a mandatory death sentence for those found guilty of distributing and trafficking most types of drugs.