The police registered an FIR against 400 unidentified persons who attacked police and a Sub Divisional Magistrate (SDM) on Sunday, sources in the police department said.
However, the sources also said that the attackers are likely to be let off on humanitarian grounds.
Around 7,000 migrant workers blocked Agra-Bombay Road in Bijasan in MP's Barwani - a red zone area -- on Sunday and attacked police, injuring the additional SP, an SDM and three other police personnel.
The migrants were angry at being blocked on the Maharashtra-MP border and demanded to be allowed to pass through MP on their way to UP, Bihar, Rajasthan and Odisha.
For the last two days, they were pressurising the Barwani administration to let them through, and squatted on Agra-Mumbai NH a few times, but were persuaded to call off the protest.
The workers were forced to leave Maharashtra for want of work and food. They were camping near Barwani. MP police had to stop them because the UP police had sealed the border at the other end on the Mumbai-Agra road.
Reports said the three migrants had died in the past few days.
Barwani collector Amit Tomar said the Uttar Pradesh authorities were being contacted to find a solution to the issue.