Two Australians were arrested for heroin trafficking as they prepared to board a flight from Vietnam to Australia, police said on Friday.
The two were identified as Australians of Vietnamese origin, Nguyen Van Huy, 37, and his wife Hoang Le Thuy, 40, and were arrested on Wednesday night at the airport in Ho Chi Minh City, police said.
They were found with 500 grams of heroin hidden in bottles of medication in their checked baggage, an officer at the anti-drug police unit said.
The couple was travelling with their three daughters, aged 2 to 10, who were released on Thursday to relatives, the police spokeswoman said.
Officials at the Australian embassy in Ho Chi Minh City were not available for comment.
A Department of Foreign Affairs and Trade spokesman in Canberra said Australian consular officials were seeking access to the couple.
Friday's Liberated Saigon newspaper quoted the two as telling police they were hired by a transnational drug trafficking ring to transport the heroin.
Vietnam has some of the harshest drug laws in the world. Possessing, trading or trafficking 600 grams of heroin or 20 kilograms of opium is punishable by death.
About a dozen Australians of Vietnamese have been brought to court in Vietnam for heroin trafficking in recent years.
However, at least four Australian-Vietnamese have had their death sentences commuted in recent years because of lobbying by the Australian government.