The Hanoi Police Department on Feb. 29 detained and searched the house of activist and blogger Nguyen Chi Tuyen to investigate his alleged engagement in “distributing anti-state propaganda,” a violation of Article 117 of the Penal Code.

Nguyen Thi Anh Tuyet, Tuyen’s wife, confirmed her husband's detention on the same day, adding that he would be held at Hanoi Detention Center No. 2 for four months during the investigation period. The police also confiscated his cell phone, a laptop, and some of his handwritten notes.

Tuyet said that the previous afternoon, her husband received a summons from the Hanoi Police Department to come in for questioning, but he declined to go because he felt unwell. Last January, the police sent Tuyen a notice informing him that he was prohibited from traveling outside Vietnam.

Tuyen, who is also known by his blog name “Anh Chi,” is a renowned environmental activist, blogger, and human rights defender who often participated in demonstrations against China’s excursions in Vietnam’s maritime territories. He also established two YouTube channels, Anh Chí Râu Đen and AC Media, that discuss social issues in Vietnam and report on Russia’s invasion of Ukraine.

Because of his activism, Tuyen became a target of harassment and surveillance by Vietnamese security. In 2015, he was hospitalized after being beaten by strangers, possibly plainclothes police.