Myanmar's government says it will investigate riots at seven prisons this week that it believes were coordinated.

The government in Sagaing region in northwestern Myanmar says it has restored control over the Shwebo township prison, where it said four prisoners had died and two others were injured, along with two prison staff.

The office of President Win Myint said in a statement that there had been riots Wednesday and Thursday at six other prisons. It said prisoners said they were dissatisfied with a recent series of mass pardons.

It said investigations would be made "to bring out the truth" because the similarity of statements from the prisons and the transmission of live video to social media from prisoners' illegal cellphones indicated "linkages and incitement."