Police have fired tear gas and water cannon and there were reports of gunfire in Myanmar’s largest city where another anti-coup protest was under way, with scores of students and other demonstrators hauled away in police trucks.

The violence erupted in the early morning on Sunday when medical students were marching in Yangon’s streets near the Hledan Center intersection, which has become the gathering point for protesters who then fan out to other parts of the city.

The sounds of gunfire and what appeared to be smoke grenades thrown into the crowds were reported.

Two protesters were killed during the crackdowns, according to local media.

The Myanmar Now media group posted a video of a wounded man lying on the street near the Hledan Centre intersection in Yangon, and said he had been “shot in his chest area by what appeared to be live ammunition”.

Police in Dawei, in the southeast, and Monywa, 135 km (85 miles) northwest of Mandalay, also used force against protesters. Both cities, with populations of less than 200,000 each, have been seeing large demonstrations.

Since the military takeover on February 1, Myanmar has been roiled by demonstrations and a civil disobedience campaign encouraging civil servants to walk off the job.

The military said it took power because last year’s polls were marred by massive irregularities. The election commission before the military seized power had refuted the allegation of widespread fraud. The military government has dismissed the old commission’s members and appointed new ones, who on Friday annulled the election results.

More than 850 people have been arrested, charged or sentenced since the coup, according to the Assistance Association for Political Prisoners monitoring group.

But an escalating crackdown by security forces is expected to raise that number dramatically, with state newspapers reporting 479 arrests on Saturday alone.