An international human rights group says a Vietnamese political prisoner has died after more than three decades in detention.
Human Rights Watch said Tuesday that Truong Van Suong died a day earlier in Ha Nam province outside Hanoi.
He was the second Vietnamese political prisoner to die since July. Nguyen Van Trai died in prison on July 11.
Foreign Ministry spokesman Luong Thanh Nghi confirmed Suong's death, saying he died from a serious illness despite receiving treatment from doctors at a hospital.
Nghi said Suong was released from prison in July last year for a year of medical parole, after which he was returned to jail in "stable health."
"By locking him up again in such terrible health, the government of Vietnam essentially condemned him to die alone, separated from family and friends in his last days," Phil Robertson, Human Rights Watch's deputy Asia director, said in a statement.
The New York-based group said Suong, 68, suffered from heart disease and high blood pressure. It said he was a soldier in the former South Vietnam who was sent to a re-education camp from 1975 to 1981 after the fall of the Saigon government. After being released, he fled to Thailand and joined an anti-communist group. He returned to Vietnam in 1983 and was immediately arrested and sentenced to life imprisonment on spying charges, it said.
The death of two political prisoners since July "should be a warning signal to the Vietnamese authorities. The government should immediately release all political prisoners unconditionally, but they should especially prioritize the release of those with serious health problems so they can receive proper medical treatment," Robertson said.