Myanmar's military authorities are cracking down with increasing severity on daily protests against their February 1 coup, with at least 70 people killed according to the UN's top rights expert on the country.

Since then a growing stream of people, many of them police refusing to take part in the crackdown, have crossed over the border into the north-eastern Indian state of Mizoram.

As of Friday, a total of 264 people had done so, including 198 police officers and family members, security officials said.

"The reason to come over from Myanmar to India is because I don't want to serve under the military junta," one of the officers, who didn't want to be identified, told AFP.

"The second reason is that if I quit from the military junta and I join with the people, I believe we can win the fight against the military junta," he said.

He added that the authorities were conducting "beating or torturing as they want".

"I have witnessed the police arresting as many people as they can see, even the people who are not joining the protest and standing on the side to just watch or take a photo," he added.

India authorities have "pushed back" eight of those who have crossed the border, the security source said. A local village chief told AFP this week that dozens of others were waiting to enter India.