By Simon Lewis and Shoon Naing
YANGON (Reuters) - Myanmar's military has engaged in deadly clashes with ethnic minority rebels in the northeast in the past week, state media reported on Wednesday, as concern grows for three reporters detained by the military in the region.
The journalists were taken into military custody in northern Shan State on Monday after covering a drug-burning event organized by the rebel Ta'ang National Liberation Army (TNLA), which demands more autonomy for the Ta'ang ethnic group.
The journalists' detention comes amid rising concern that press freedoms are being eroded in Myanmar despite a transition from full military rule, and underlines the challenge de facto leader Aung San Suu Kyi faces in achieving peace.
Clashes between government troops and loosely allied rebel groups close to Myanmar's border with China have set back peace talks prioritized by Suu Kyi when she took power last year.
The state-run Global New Light of Myanmar newspaper said the army - known as the Tatmadaw - had clashed five times with insurgents since the army discovered a TNLA training camp on June 20.
"During the engagements, several Tatmadaw officers and troops were killed and a few were wounded. Four bodies of enemy troops were also found," the newspaper said, citing unidentified military officials.
The clashes took place while the three journalists were in the TNLA zone for the drug-burning.
Two community groups said on Tuesday they had documented extrajudicial killings, mass detention of civilians and torture by the military in recent days.
In a statement, the Ta'ang Women's Organization and the Ta'ang Students and Youth Organization also said the military was responsible for mortar strikes that killed two villagers and wounded one on Monday.
Military spokesmen were not immediately available for comment. The army almost always rejects accusations of rights abuses although it has in recent years acknowledged occasional violations by soldiers and promised action.
In a separate report, the Global New Light of Myanmar said the TNLA and the Kachin Independence Army were responsible for the attack on the villagers, citing the office of the commander in chief, Senior General Min Aung Hlaing.
The military has not disclosed the exact whereabouts of the three reporters - Aye Nai and Pyae Phone Naing of Democratic Voice of Burma and Lawi Weng, a senior reporter with the Irrawaddy magazine.
Both publications, which operate in English and Burmese, were formed in exile during military rule but have set up bureaus in the commercial hub Yangon since pre-publication censorship was officially abolished in 2012.
Lawi Weng is among the most experienced journalists covering Myanmar's conflicts, and has reported from TNLA-controlled territory in the past.
Suu Kyi's spokesman said on Tuesday the three would be charged with a colonial-era Unlawful Associations Act that outlaws contact with rebel groups.
They were being held at a military facility but would be transferred to police custody within days, said Zaw Htay, the spokesman.
The group the Committee to Protect Journalists said the three should be released immediately and allowed to carry on with their work.
"Using the archaic Unlawful Associations Act to incarcerate journalists is an affront to democracy in Myanmar," the group's Asia Program Coordinator Steven Butler said in a statement.
Following landmark elections in 2015, Nobel laureate Suu Kyi came to power last year after decades of rule by military generals or their proxies.
Suu Kyi does not have oversight over the armed forces, but she has not used her party's parliamentary majority to repeal many of the laws used by previous regimes to stifle dissent.
Journalists demonstrated in Yangon this month against what they said were increasing curbs on free speech, especially the use of a telecommunications law to prosecute reporters and social media users for defamation.
(Reporting by Simon Lewis and Shoon Naing; Editing by Robert Birsel)