PHNOM PENH, Cambodia — A former Cambodian opposition lawmaker who has been a strong critic of the government's handling of demarcating the border with neighboring Vietnam has been pardoned by the country's king.

Um Sam An, a member of the now-dissolved opposition Cambodia National Rescue Party, was sentenced in October 2016 to 2 1/2 years in prison for making comments on the politically sensitive topic and implying that Prime Minister Hun Sen's government failed to counter land encroachment by Vietnam, Cambodia's traditional enemy.

In a letter on Saturday, King Norodom Sihamoni said Um Sam An had been granted amnesty from his jail term. The amnesty was granted at the request of Hun Sen.

In handing out the sentence in 2016, a judge said the accusations made by Um Sam An in 2015 Facebook posts aimed to cause chaos in society. The lawmaker was arrested in April 2016 in the Cambodian city of Siem Reap after having returned from a trip to the United States.

Um Sam An is the latest political prisoner to be released from jail in the last week.

On Tuesday, two Cambodian journalists who had worked for U.S.-funded Radio Free Asia and who have been charged with espionage were released on bail. A day earlier, four women jailed for participating in Cambodia's land rights movement were freed under a royal pardon requested by Hun Sen.

Hun Sen cracked down on critics and opponents last year in what was seen as an effort to ensure his party would win elections held this year. His party did win last month's polls, though the vote was widely seen as lacking credibility.

Hun Sen, who has been in office since 1985 and has held a tight grip on power since ousting a co-prime minister in a bloody 1997 coup, has a record of cracking down harshly when facing a serious challenge, then effecting reconciliation when he no longer feels threatened. The pattern keeps human rights groups and Western governments off balance and moderates their criticism.