Two local journalists working for the international news organization Reuters in Myanmar have been arrested in Yangon, a government spokesperson said on Wednesday.

Journalists Wa Lone and Kyaw Soe Oo were arrested late Tuesday and were charged with violating Section 3.1 of the country's colonial-era Official Secrets Act.

"Yes, it is correct that they were arrested," government spokesman Zaw Htay said. "Not only your reporters but also the policemen who were involved in that case. We will take action against those policemen and also the reporters."

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Violations of the Official Secrets Act, which dates back to the 1920s, are punishable by up to 14 years in prison.

Yangon-based Frontier Myanmar magazine and the Associated Press reported that the arrests were made after police found the two were found in possession of copies of documents from officials in Muangdaw district, which were related to the ongoing crisis in Rakhine state.

Reuters said in a statement that Wa Lone and Kyaw Soe Oo had been missing since late Tuesday night. "We have filed a missing person's report and are doing everything we can to locate them," the statement said.

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The US Embassy in Yangon said in a statement that it was "deeply concerned by the highly irregular arrests of two Reuters reporters after they were invited to meet with police officials in Yangon last night."

"For a democracy to succeed, journalists need to be able to do their jobs freely," the US statement said. "We urge the government to explain these arrests and allow immediate access to the journalists.”

According to Reuters, Wa Lone, who joined the news agency in June 2016, has covered a range of stories, including the Rohingya refugee crisis in Rakhine State. Kyaw Soe Oo has reported for Reuters since September. 

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Northern Rakhine state is the epicenter of the Myanmar military's brutal security operation that has forced more than 625,000 minority Rohingya Muslims to flee to neighboring Bangladesh.

The campaign launched in August in response to attacks on police outposts has been condemned by the United Nations as "ethnic cleansing" and those fleeing have described widespread rights abuses by security forces.

Media freedom ‘getting worse'

The military, which is in charge of security in northern Rakhine, and the civilian government have barred most journalists and international observers from independently traveling to the region.

Two foreign journalists along with two of their Myanmar associates are currently awaiting trial on new charges after already being sentenced to jail for illegally flying a drone over parliament.

"Media freedom in the country is getting worse and arresting journalists is more and more common these days, and this shows that the authorities are clearly ignoring media laws," said Robert Sann Aung, a human rights lawyer.

law/sms (AP, dpa, Reuters)