HANOI (Reuters) - A court in Vietnam has jailed a journalist known for his criticism of the ruling Communist Party for 10 years over a land deal dating from the early 2000s that authorities had deemed illegal, state media said on Tuesday.

Truong Duy Nhat was arrested in Vietnam last year after disappearing in Thailand, fanning fears that officials in Southeast Asian countries have been cooperating to track down and arrest each others’ exiled dissidents.

The Hanoi People’s Court said Nhat abused his position as the branch head of a state news outlet to help a disgraced business tycoon illegally acquire land from 2003 to 2004, the Ministry of Public Security said after Monday’s trial.

It was not immediately clear who was defending Nhat at the trial. Telephone calls to the Hanoi People’s Court went unanswered on Tuesday.

The sale of the plot, which was under the control of the Danang branch of the state-run Dai Doan Ket newspaper, caused losses of 13 billion dong ($561,000), the ministry said in its statement.

Nhat, who is also a contributor to Washington-based Radio Free Asia (RFA), had already served a two-year prison term after a 2014 trial over accusations of “abusing democratic freedoms to infringe upon the interests of the state”, the ministry said.

The statement did not refer to any of Nhat’s journalism or his contributions to RFA or its website, which remains blocked in Vietnam.

In an emailed statement, RFA said Nhat’s lawyer was convicted of tax evasion in November 2019.

The president of RFA, Bay Fang, condemned the sentence.

“This miscarriage of justice only reinforces RFA’s mission to provide the people of Vietnam with uncensored perspectives, and accurate news and information,” RFA quoted Fang as saying in the statement.

Phan Van Anh Vu, a business tycoon accused of collusion with Nhat, had fled to Singapore seeking passage to Germany, but was arrested in Vietnam in early 2018.

He was sentenced to a total of at least 66 years in jail at several trials on separate charges ranging from deliberate disclosure of state secrets to abuse of power to acquire property and violations of state asset management rules.