Ho Thi Bich Khuong, 44, received three years house arrest on top of her five year term, and Nguyen Trung Ton, 40, was given a similar extra penalty of two years, the Communist Party newspaper Nhan Dan reported.

Their one-day trial took place on Thursday in the central province of Nghe An, it said.

Both were arrested on November 15 for "collecting documents and writing articles which tarnished the reputation of the Communist Party and the Socialist regime", according to the report.

The Communist Party is the only authorised political party in Vietnam.

Khuong was also accused of giving interviews to foreign radio stations against the state, posting them on the Internet and of belonging to several human rights groups involving "reactionary" people.

She was sentenced in April 2008 to two years in jail for "abusing democratic freedoms to infringe upon the interests of the State".

Rights groups say dozens of peaceful political critics and rights campaigners have been sentenced to long prison terms in Vietnam since the one-party state launched a crackdown on free expression in late 2009.

US Secretary of State Hillary Clinton said last month that Vietnam must improve its human rights record.

Agence France Presse - December 30, 2011