Vietnamese police have arrested seven people suspected of involvement in the bombing last month of a police station in the Southeast Asian country's largest city.
The blast in Ho Chi Minh City injured a policewoman and damaged some property.
The online newspaper VnExpress reported today that four suspects were accused of conducting terrorist activities aimed at overthrowing the "people's administration" and 3 were accused of illegally trading explosives.
Police also seized 10 kilograms (22 pounds) of explosives and 8 homemade bombs.
The paper quoted Maj. Gen. Phan Anh Minh, the city's deputy police chief, as saying that the group collaborated with the "reactionary" Viet Nguyen Dynasty group in exile in the US.
Bomb blasts are rare in Communist-ruled Vietnam where authorities maintain tight control over almost all aspects of life.