Myanmar's press council says the army has admitted to shooting dead a man in its custody who activists claim was a reporter detained after covering clashes near the conflict-hit eastern border.

Aung Naing was gunned down as he tried to flee detention on October 4, the interim Myanmar Press Council said citing a rare statement issued by the military.

He "tried to escape by fighting with a soldier and attempting to steal his weapon" said the document, adding that Aung Naing was suspected of being a member of a local armed group.

This was contradicted by activists and local media reports which said he was a freelance journalist covering unrest in the region, where fighting between government troops and rebels has flared in recent weeks.