A court in northern Vietnam has sentenced an activist to 13 years in prison after finding him guilty of attempting to overthrow the government. He is the seventh activist to be jailed in the past week as Communist authorities step up a crackdown on dissent.

The official Vietnam News Agency says Nguyen Van Tuc was convicted of affiliating with an outlawed group named Brotherhood for Democracy in a half-day trial Tuesday at the People's Court in Thai Binh province. Tuc was also ordered to serve three years of house arrest after finishing his prison sentence.

Tuc was sentenced in 2009 to four years in prison for distributing anti-government propaganda.

Last week, six members of the group were sentenced to seven to 15 years in prison on the same charges.