Since the coup, more than 60 people have been killed as security forces have broken up anti-coup demonstrations
People barricaded in a Yangon neighbourhood overnight said on Tuesday that security forces searched their homes room by room for anti-coup protesters, targeting apartments flying the flag of Aung San Suu Kyi's party.
Myanmar has been in turmoil since the military ousted and detained Suu Kyi last month, triggering daily protests around the country to demand the junta restore democracy.
The police and army have responded with an increasingly brutal crackdown and parts of Yangon have emerged as flashpoints for violence as protesters continue to defy authorities and take to the streets.
Crowds once again flocked to central San Chaung township in the commercial hub to call for Suu Kyi's release from custody in a Monday protest coiciding with International Women's Day.
By nightfall, security forces had sealed off a block of streets with around 200 protesters still inside, according to the UN rights office, prompting alarm from diplomatic missions and calls for their safe release.
Sharp loud bangs were heard coming from the area, although it was not clear if the sounds were caused by gunfire or stun grenades.
Security forces started searching apartments after a nightly internet shutdown blanketed the country at 1830 GMT, residents told AFP, particularly those flying the red and gold flag of Suu Kyi's National League for Democracy (NLD) party on their balconies.
One resident said her home -- which did not have any protesters hiding inside -- was searched.
"They searched every building on Kyun Taw road -- they destroyed the locks of apartment buildings if they were locked downstairs," said the resident, adding that she heard dozens were arrested.
By dawn, security forces appeared to have retreated, allowing some protesters to escape from the area.
'There will be a crackdown again'
San Chaung -- a bustling township known for its cafes, bars and restaurants -- has transformed since the protests began, with makeshift barricades of bamboo, sandbags, tables and barbed wire set up by protesters in an effort to slow security forces. On Tuesday morning saw brisk sales from food vendors on the streets.
"We need to finish selling our goods before 9am -- there will be a crackdown again on the streets," said one.
Since the coup, more than 60 people have been killed as security forces have broken up anti-coup demonstrations, according to the Assistance Association for Political Prisoners monitoring group.
The move to seal off streets in San Chaung prompted embassies in Yangon -- including those of the United States and former colonial power Britain -- to urge security forces to free the demonstrators.
The UN Secretary General Antonio Guterres called for "maximum restraint," urging the "safe release of all without violence or arrests."
The Monday night raids in San Chaung came after three protesters were shot dead at rallies on a day when many shops, factories and banks closed as part of a general strike to protest against the coup.
The military has denied responsibility for loss of life in the protests and defended seizing power by alleging widespread electoral fraud in November's elections, which Suu Kyi's party had won in a landslide.