BANGKOK (CNS) — The mother of a prominent Catholic blogger died after setting herself on fire to protest her daughter’s detention for allegedly spreading anti-government propaganda, activists said.

Dang Thi Kim Lieng, 64, set herself aflame near a local government office building in the southern city of Bac Lieu July 30, reported the Asian church news agency UCA News.

“Her wounds were very serious and she died on the way to the hospital (in Ho Chi Minh City),” said Redemptorist Father Dinh Huu Thoai, a friend of the family.

Her daughter, Marie Ta Phong Tan, has been detained in jail since her arrest in September 2011 on charges of conducting propaganda against the state.

The 43-year-old Catholic former policewoman was one of three bloggers arrested in a government crackdown. Their trials were scheduled to begin Aug. 7.

The trio of bloggers belongs to the outlawed Free Vietnamese Journalists’ Club. They are accused of posting hundreds of articles that “distort and opposed” Vietnam’s communist government. Their work regularly appeared on Cong Ly va Su That (Justice and Truth), a blog that addressed social justice issues.

The U.S. Embassy in Hanoi said it was “deeply concerned” by Lieng’s death.

“We call upon the government of Vietnam to release all three immediately,” the embassy said in a statement. It also called on Hanoi to create a society where journalists could operate freely and without fear.

Lieng had not seen her daughter since her arrest. Local church sources said she had been worried about her daughter’s upcoming trial.

She also had been questioned by authorities, and her home and movements were under round-the-clock surveillance, the sources said.

Lieng’s death, the first reported self-immolation in Vietnam since the 1970s, came a day after the Vietnamese Redemptorist News network called for the release of 17 Christians, including Tan, some of whom have been held without trial since July 2011.

In a statement July 29, the network said most of the detainees had contributed to its blog http://www.chuacuuthe.com/. It claimed they were not arrested in accordance with due process under Vietnamese law or according to international conventions signed by Vietnam.

“Their ongoing detention in silence indicates a serious violation against the spirit of the call to construct a state of jurisdiction,” said the statement signed by two Redemptorist priests, Father Anthony Le Ngoc Thanh, head of the network, and Father Joseph Dinh Huu Thoai, head of the Vietnam Redemptorist provincial office.

The statement denied that the bloggers were spreading anti-government propaganda, saying they were “all righteous people.”

“They were simply concerned for the fate of our country, attended courses on communications and blogged to bring justice and truth to people. They served the public through social and charitable work,” the statement concluded.