Authorities in central Vietnam’s Quang Binh province have arrested yet another member of an online democracy advocacy group.

Vietnamese online website VN Express cited a press release issued by Quang Binh police as saying Nguyen Trung Truc, 43, is charged with “carrying out activities aimed at overthrowing the people’s administration” under Article 79 of Vietnam’s Penal Code.

The former political prisoner is allegedly a key member and the spokesperson of Hoi Anh Em Dan Chu (Brotherhood For Democracy), an online organisation accused of trying to overthrow the government.

Truc’s son told RFA’s Vietnamese Service that about 100 uniformed and plainclothes officers arrived at their house around 9am on Friday.

“They pulled my father outside to take video and photos, and then they forced him to sign some documents. Then they searched our house and took our phones and papers,” he told RFA.

“They spent three hours doing all of this, then they took him away at about 1.00 pm after reading a document accusing my father of having violated Article 79″.

Another member of Quang Binh province’s Brotherhood for Democracy confirmed to RFA that Truc had been arrested after about 100 officials went to Truc’s house and conducted a house search.

Last Sunday, Vietnamese police arrested four other members of the group on similar anti-state charges.

The activists were identified as Protestant pastor Nguyen Trung Ton, 45, engineer Pham Van Troi, 45, journalist Truong Minh Duc, 57, and lawyer Nguyen Bac Truyen, 49.

Despite sweeping reforms to Vietnam‘s economy and growing openness to social change, the Communist Party does not tolerate criticism.

At the end of last month, police from the central province of Nghe An arrested Le Dinh Luong, 51, on suspicion of violating Article 79 of Vietnam’s penal code.

In the same month, a court in the northern province of Ha Nam sentenced blogger Tran Thi Nga, 40, to nine years in prison for posting anti-state propaganda material on the internet.

In June, one of Vietnam‘s most prominent bloggers, Nguyen Ngoc Nhu Quynh, 38, – known as Mother Mushroom – was jailed for 10 years.