Pham Doan Trang, a Vietnamese writer and blogger who advocates for democracy, has been arrested for carrying out anti-state activities.
This closely followed the US-Vietnam Human Rights Dialogue, with Human Rights Watch and Amnesty International having demanded the release of Ms Trang as she faces up to 20 years of jail if convicted.
The one party communist state has a history of jailing critics and dissidents, who in the age of social media have been able to share their pro-democracy views in Vietnam, which heavily controls press and media.