Wa Lone, 32, and Kyaw Soe Oo, 28, were arrested in December shortly after being given official documents by police. They have maintained their innocence and say they were framed.
The case has prompted international outrage, with the United Nations, the European Union, the United States and press freedom campaigners around the world all calling for the release of the reporters, who are both Myanmar nationals.
“Today is a sad day for Myanmar, Reuters journalists Wa Lone and Kyaw Soe Oo, and the press everywhere,” said the news agency’s editor-in-chief Stephen J Adler.
He added: “These two admirable reporters have already spent nearly nine months in prison on false charges designed to silence their reporting and intimidate the press.
“Without any evidence of wrongdoing and in the face of compelling evidence of a police set-up, today’s ruling condemns them to the continued loss of their freedom and condones the misconduct of security forces.”
The journalists were detained while looking into the killing of 10 Rohingya men by Myanmar soldiers and Buddhist villagers, as well as other abuses by police and troops, at Inn Din, a town in the country’s troubled Rakhine state.
They told a court in Yangon that two police officials handed them papers at a restaurant in the city moments before other officers arrested them.
One police witness testified that the restaurant meeting was a set-up to entrap the journalists to stop or punish them for their reporting.
Sentencing the reporters, who were charged with breaching the Official Secrets Act, judge Ye Lwin said “confidential documents” found on them were “not public information” and would have been useful “to enemies of the state and terrorist organisations”.
Kyaw Soe Oo’s wife broke down into tears as the verdicts were read out in a small and stifling courtroom packed with at least 50 people, with others crowded outside.
Wa Lone, wearing handcuffs and flanked by police, told supporters not to worry as he addressed a cluster of friends, family and reporters.
“We know what we did. We know we did nothing wrong,” he said. “I have no fear. I believe in justice, democracy and freedom.”
Kyaw Soe Oo said the journalists would continue their fight for press freedom.
“What I want to say to the government is: you can put us in jail, but do not close the eyes and ears of the people,” he added.
Both reporters have young daughters and have not seen their families outside of prison visits and court hearings for nearly nine months.
Kyaw Soe Oo has a three-year-old daughter and Wa Lone’s wife, Pan Ei Mon, gave birth to their first child last month.
Myanmar government spokesman Zaw Htay did not respond to requests for comment about the verdict.
He has mostly declined to comment throughout the proceedings, saying the courts were independent and the case would be conducted according to the law.
The jailing of the journalists comes amid mounting pressure on the government of Nobel Peace Prize winner Aung San Suu Kyi over the alleged genocide of Rohingya Muslim insurgents by Myanmar’s army.
More than 700,000 Rohingya have fled across the country’s western border into Bangladesh since Myanmar’s army began a brutal crackdown on the minority in late 2016.
“It’s thanks to the bravery of journalists like Wa Lone and Kyaw Soe Oo that the military’s atrocities have been exposed,” said Tirana Hassan, Amnesty International’s director of crisis response.
“Instead of targeting these two journalists, the Myanmar authorities should have been going after those responsible for killings, rape, torture and the torching of hundreds of Rohingya villages.”
She added: “Today’s verdict cannot conceal the truth of what happened in Rakhine State.”
Dozens of journalists and pro-democracy activists marched in Yangon, Myanmar’s capital and largest city, in support of the reporters on Saturday.
But in the country at large, which has an overwhelming Buddhist majority, there is widespread prejudice against the Rohingya, and in the government and military there is near-xenophobic sensitivity to foreign criticism.
Myanmar’s courts are one of the country’s most conservative and nationalistic institutions.
Earlier this year the court declined to halt the trial after an initial presentation of evidence, even though a policeman called as a prosecution witness testified that his commander had ordered that documents be planted on the journalists.
After his testimony, the officer was jailed for a year for violating police regulations and his family was kicked out of police housing.
Other testimony by prosecution witnesses was contradictory and the documents presented as evidence against the reporters appeared to be neither secret nor sensitive.
The journalists said they did not solicit or knowingly possess any secret documents.
Dan Chugg, the UK’s ambassador to Myanmar, said the verdicts “dealt a hammer blow for the rule of law”.
“Freedom of expression and rule of law are fundamental in a democracy, and this case has passed a long shadow over both today,” he added. “The judge has appeared to have ignored evidence and to have ignored Myanmar law.”
US ambassador Scot Marciel, who attended the hearing, said the reporters’ imprisonment was “deeply troubling for everybody who has struggled so hard here for media freedom”.
He suggested the verdicts would “decrease the confidence the people of Myanmar have in their justice system”.
UN humanitarian coordinator in Myanmar, Knut Ostby, said: “The United Nations has consistently called for the release of the Reuters journalists and urged the authorities to respect their right to pursue freedom of expression and information.
“Wa Lone and Kyaw Soe Oo should be allowed to return to their families and continue their work as journalists.”
UN investigators, working on behalf of the body’s Human Rights Council, last week declared for the first time that violence against Rohingya in Myanmar was genocide.
They called for the army’s commander-in-chief and five other named generals to face prosecution for crimes against humanity and war crimes.
Myanmar rejected the report and said its military had been responding legitimately to attacks by Rohingya insurgents.
The International Criminal Court is considering whether it has jurisdiction over events in Rakhine, while the United States, the European Union and Canada have sanctioned Myanmar over the crackdown.
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