At least 50 government troops occupied a Catholic church in the town of Moebye in the southern Shan State, local media reported.
The junta soldiers reportedly took control of the Holy Mother of God Cathedral since July 18.
Priests, nuns, and students who were in the church when the soldiers arrived were detained and not released until around 8 a.m. the next day, said a report on the news site Myanmar Now.
Myanmar’s military has been accused of targeting churches in parts of the country with large Christian communities.
In May last year, the soldiers shelled a Catholic church near the Karenni State capital Loikaw, killing four and critically injuring eight.
This week, Radio Free Asia reported that military troops have killed at least six people in a raid on a village in Myanmar’s Sagaing region.
Sources from Salingyi township’s Yae Mein (South) village said the bodies of six men were discovered when residents returned to the area on Wednesday following the raid a day earlier.
It was not immediately clear which military battalion was responsible for the raid and the killings.
A Salingyi-based member of parliament for Sagaing region, who requested anonymity for security reasons, said the killings in Yae Mein (South) village amounted to a “war crime.”
“The military no longer sees members of the public as citizens, but as enemies,” they said.
This year has seen an upsurge in arson attacks and killings in Myanmar’s Magway and Sagaing regions as violence has spiraled between junta forces and the insurgents.
Last month, independent research group Data For Myanmar, which studies the effects of conflict on communities, said that at least 18,886 houses had been destroyed by military arson across the country since the coup.