LONG BEACH, Calif. — Meach Sovannara didn’t know it, but the last time he would see his family for three years was before boarding a plane bound for Cambodia in the summer of 2015.

A political activist, Meach had traveled to his home country from the United States before. But he returned in 2015 to be tried for his participation in a 2014 demonstration where he gave a speech about freedom of speech and democracy, he said. The protest became violent, Reuters reported, and Meach was arrested and imprisoned for five months before being released on bail in April 2015.

In Cambodia, Meach was charged with participating in and leading an insurrectory movement, according to Amnesty International. He was sentenced to 20 years in prison.

Meach's sentence was cut short after Cambodian King Norodom Sihamoni issued a royal decree pardoning him and 13 others in August following an election in July.

“They exploited that situation and accused me of criminal insurrection,” Meach, sitting in his Long Beach home, said through an interpreter, Bo Uce, a friend of Meach and a former interpreter for the Los Angeles Superior Court.

Meach wasn't surprised.

Meach Sovannara, a former spokesman of the opposition Cambodia National Rescue Party, holds burned incense sticks to pray on the outskirts of Phnom Penh, Cambodia on Aug. 28, 2018. Heng Sinith / AP file

For approximately three decades, Cambodia has been ruled by the Cambodian People's Party (CPP) and Prime Minister Hun Sen. Under his leadership, critics say opposition party members, journalists and many others have been arrested, beaten, harassed and intimidated.

"What we are facing is tyranny in Cambodia, a dictatorial regime," Meach said.

Before moving to the United States 15 years ago, Meach worked as a journalist at U.S.-funded Radio Free Asia, where he covered government corruption and rule-of-law violations, he said. His reporting resulted in a death threat in 2003 that led him and his family to flee to the United States, where they sought asylum, he added.

He also became an official for Cambodia's main opposition party, the Cambodia National Rescue Party (CNRP), which made some electoral gains before being dissolved by the government in 2017.

Afterward, the CPP won all 125 National Assembly seats in the 2018 elections.

Prey Sar prison

Meach served his sentence at Prey Sar prison, a facility that Morton Sklar, an attorney for Sovannara and founding executive director emeritus of Human Rights USA, called a "hellhole" where inmates lack adequate food, healthcare, and room.

But the experience Meach described was different: He said he was treated well by the wardens and noted that he and other prisoners were regularly visited by nonprofits to ensure they were in good health and being treated humanely. Naly Pilorge, director of the Cambodian human rights nonprofit Cambodian League for the Promotion and Defense of Human Rights, said in an email that the group's medical team and prison researchers regularly visit Prey Sar. The U.S. Embassy in Phnom Penh also said it regularly checks on American prisoners.

While confined, Meach continued his activism. He said he educated about 50 to 100 other prisoners about dictatorships, communism, freedom and what characteristics make good leaders. He stayed up to date on politics by reading newspapers, watching TV and listening to the radio, and helped prisoners purchase their own radios so that they could stay updated on current events, he said.

His experiences at Prey Sar prompted him to draft a book that he said will discuss life in prison, prisoners being falsely accused, how — based on his observation — most political prisoners are opposition party members, and suggestions on how reforms for democracy, freedom and justice should be executed.

Early release

Meach's time behind bars came to an early end shortly after the CPP's victory in July. He and 13 other members of the CNRP were pardoned by the Cambodian king in August.

According to The Phnom Penh Post, the release came after 12 of the 14, including Meach, wrote a letter to Hun Sen expressing regret for participating in the 2014 demonstration “which seriously affected security and social order.” They also pledged not to “join any demonstration or any activity with such consideration.”

A former member of the now-disbanded opposition Cambodia National Rescue Party Meach Sovannara sits in a restaurant on the outskirts of Phnom Penh, Cambodia on Aug. 28, 2018. Heng Sinith / AP file

Sklar, the attorney, said the release of the prisoners should be celebrated, but called it “an entirely politically motivated move” that was long overdue.

“They never should have been arrested or imprisoned in the first place,” he said. “Hun Sen’s actions to release the prisoners now, while welcome, is simply part of his plan to maintain his power indefinitely.”

Cambodia's Ministry of Justice did not respond to NBC News requests for comment.

Meach arrived in California on Sept. 8, reuniting with his wife and three daughters.

“I'm excited,” he said about being home, “happy to meet my family, friends and to come back and to have freedom.”

His schedule has been filled over the next several months with domestic and international travel plans to meet with members of the Cambodian community who supported him while he was in Prey Sar, he said.

"I would like to thank them to help me continue the fight for democracy, justice and human rights; also thank them and express my gratitude," he said. "When I was in prison, they sent money to support me and other political prisoners and activists.... And I will tell them that my fight is not over yet."

He also plans to finalize and publish his book before the end of the year.

But perhaps more than anything, Meach remains determined to continue fighting for democracy, human rights and freedom in Cambodia. Despite the risks involved, he said he plans to return to his home country and to continue his activism.

“If Cambodians continue to have a dictatorship, tyranny, and if those sycophants genuflect and kowtow to this particular dictator, nothing will change because corruption, injustice will always be prevalent,” he said.

“To really have democracy and fair elections in Cambodia, if I don’t continue, who will do it if I don’t do it?” he added.

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