Prison department director Min Tun Soe said the riots were triggered over the inmate anger at not being included in the amnesty
Four prisoners were killed during a riot at a northern Myanmar jail, officials said Thursday, coming on the heels of an amnesty which saw more than 6,000 inmates released - including high-profile Reuters reporters Wa Lone and Kyaw Soe Oo.
The unrest at Sagaing region's Shwe Bo prison began on Wednesday evening, said chief minister Myint Naing.
"They were demanding for equal rights. They became anarchic," he said, adding that everything was now "under control."
Myint did not say how the prisoners died.
Military spokesman Zaw Min Tun said border affairs officials were called in to "control" the situation.
"We heard there was some shooting," he said, adding that there were also reports of unrest in jails in Karen and Kachin states.
The violence in Shwe Bo comes days after more than 6,000 people were freed in the latest round of presidential pardons - part of an annual prisoner amnesty granted by Myanmar President Win Myint.
According to local newspaper Eleven Media, prison department director Min Tun Soe said the riots were triggered over the inmate anger at not being included in the amnesty.
In total, 23,000 prisoners were released in three rounds of pardons since April 17.
The majority of those released are usually serving time for petty drug crimes, but Tuesday's release included Reuters reporters Wa Lone and Kyaw Soe Oo, who were jailed after reporting on the Rohingya crisis in northern Rakhine state.
Myanmar has freed thousands since a military junta ceded power in 2011 after five decades of brutal repression.
Former prisoners have denounced conditions in Myanmar's overcrowded prisons as abysmal.