Nguyen Hoai Phong, 23, Hoang Cong Thinh, 25, Ngo The Bao Ngoc, 26, Vuong Van Tuan, 43, and Tran Thi Le, 43, allegedly smuggled dozens of kilograms of synthetic drugs from Cambodia to Saigon and concealed them in several apartments, the local police said.
Phong, Thinh and Ngoc are believed to be the masterminds.
Earlier this month a police raid of an apartment in Sunrise City View on Nguyen Huu Tho Street, District 7, found Thinh and Phong selling drugs to husband and wife Tuan and Le. They also found eight kilograms of drugs, 16 rounds of ammunitions and several guns there.
Ngoc was caught carrying a briefcase in Cu Chi District with 14 kilograms and 20,000 pills of synthetic drugs.
A raid of his apartment on Hoang Dieu Street, District 4, turned up more drugs and a pistol with five bullets.
The police are investigating.
In Binh Phuoc Province near HCMC, a bus driver and his assistant were detained near a border gate in Loc Ninh District after authorities found 15 kilograms of meth hidden in their vehicle, which was coming from Laos.
The drugs had been sent by an unidentified person in Laos to Vietnam, the duo admitted.
Vietnam is a key trafficking hub for narcotics from the Golden Triangle, an intersection of China, Laos, Thailand, and Myanmar that is the world's second largest drug producing area after the Golden Crescent in South Asia.
Despite the country having some of the world's toughtest drug laws, including dealth penalty for smuggling and trading, drug operations have been busted almost every week.