Security forces were also deployed at hospitals and universities, state media said.
Two of the victims died of gunshot wounds to the head in the northern town of Myitkyina, the witnesses said. It was not immediately clear who fired on the protesters although both police and the military were at the scene.
Photos posted on Facebook showed the bodies of two men lying on the street. Witnesses said they were taking part in a protest against the coup when police fired stun grenades and tear gas. Several people were then hit by gunfire from nearby buildings.
One witness, who said he helped move the bodies, told Reuters two people were shot in the head and died on the spot. Three people were wounded.
“How inhumane to kill unarmed civilians,” said the witness, a 20-year-old man. “We must have our right to protest peacefully.”
At least one person was killed and two injured during a protest in the town of Phyar Pon in the Irrawaddy Delta, a political activist and local media said.
Police and military have killed more than 50 people to quell the daily demonstrations and strikes against the Feb. 1 coup, according to the United Nations.
A military spokesman did not respond to calls asking for comment on the latest incidents. Police in Myitkyina and Phyar Pon also did not respond to calls.
Myanmar has been in turmoil since the army overthrew the elected government of longtime democracy champion Aung San Suu Kyi and detained her and other political figures.
The generals say they acted because an election in November which saw Suu Kyi’s National League for Democrcay (NLD) secure a big victory was marred by fraud - a claim rejected by the electoral commission.
They have promised to hold another election, without giving a date. In the meantime, security forces have cracked down hard on widespread pro-democracy protests in a country that has a history of military rule and crushing of dissent.
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