Two lawyers have been ambushed and beaten up by assailants riding motorcycles, after taking up the case of a teenager who died in police custody.
Tran Thu Nam and Le Luan said they were driving from the home of the victim’s mother when they were intercepted by eight masked men on motorcycles.
They tried to run away into a nearby paddy field but were caught and beaten.
Both sustained injuries, with Mr Nam suffering cuts to his head and face.
They said they had recognised one of the assailants as a local police officer.
The lawyers have been providing free legal assistance to the family of Do Dang Du, a 17-year-old boy who was taken to hospital in a coma, and later died, after being held in police custody for two months on a charge of petty theft.
There have been allegations that Du sustained his injuries during beatings by the police.
An official police newspaper said that he had been attacked by a fellow inmate.
Mr Nam has questioned the validity of the autopsy carried out on Du’s body, saying that there was no examination of internal organs thought to have been damaged in the beatings.
He is one of seven lawyers who offered free legal services to the family, and demanded a full investigation into the death.
Six of the lawyers, however, were denied permission to practice, raising further suspicion about the handling of the case.
An official report by the Ministry of Public Security has acknowledged that 226 people died in detention centres around the country from 2011 to 2014.
No one has been held liable for any of the deaths.