Nguyen Hai Long, a resident of the Czech Republic, says he helped Vietnamese secret police grab Trinh Xuan Thanh, now serving two life terms in Vietnam.
He Guokuang, known by his artistic nickname Cangying, had likely been inspired by an earlier protest in Shanghai.
Residents say they could lose access to official documents such as land titles and birth certificates.
An ethnic militia accuses the government army of killing the women and dumping their bodies in a forested area.
The three-month suspension doesn't affect the paper's print version, however.
They say the exchange of information fostered by the firms is at risk amid a clampdown in the country.
The sealing of the offices of the Unirule Institute of Economics is part of a long-term strategy targeting intellectuals, a leading scholar says.
The city's government says the pro-independence Hong Kong National Party could be outlawed 'in the interests of national security.'
The country's civilian government must work harder to resolve claims and prevent further abuses, the rights group says.
ARSA insurgents were involved in some of the brutal killings, refugees allege.
Government representatives 'try to change the conversation,' one rights group says.
The former military police officer had posted claims on Facebook that he was fired over the case.