Cambodian police have confiscated nearly 1.5 tons of marijuana in what they say is their biggest seizure of the drug since they started cracking down on it 15 years ago.

The head of the Interior Ministry's anti-drug unit, Gen. Khieu Samon, told reporters Tuesday that the marijuana came from Laos and was supposed to be shipped to a third country that he refused to name, saying the case remained under investigation. He added that police were seeking to arrest the suspected mastermind, whom he described as a Westerner without revealing more details.

He said the marijuana is worth about $7 million.

Cambodia in recent years has become a transshipment point for illegal drugs because of its porous borders and lax law enforcement.