Founder of Independent Journalist Association of Vietnam and VOA contributor jailed alongside two others by Ho Chi Minh City court.
New decree that imposes fines and suspension orders for sharing 'harmful' content seen as part of wider crackdown in Vietnam on independent voices.
The jailing of Independent Journalists Association members and suspension of a news website suggest authorities are suppressing criticism in lead-up to party congress.
Environmental activist Bach Hong Quyen says the government continues to harass his family and he is considering settling outside Vietnam.
First lady Melania Trump presented Mother Mushroom, or Nguyen Ngoc Nhu Quynh, with an International Woman of Courage Award in March, in part for her environmental campaigning.