Police vehicles barricade a road outside Sule Pagoda, next to Yangon City Hall in Yangon, Myanmar on February 16. Photo: AFP

Thousands of opponents to Myanmar's February 1 military upheaval gathered again on Sunday in towns from north to south, undeterred by the bloodiest episode of their campaign the previous day when police and soldiers opened fire in the city of Mandalay, killing two.

Early on Sunday, police arrested a famous actor wanted for supporting opposition to the upheaval, his wife said, while Facebook deleted the military's main page under its standards prohibiting the incitement of violence.

The military has been unable to quell the demonstrations and a civil disobedience campaign of strikes against the upheaval and the detention of elected leader Aung San Suu Kyi and others, even with a promise of a new election, arrests and warnings against dissent.

In the main city of Yangon, several thousand young people gathered at two sites to chant slogans, while hundreds massed peacefully in the second city of Mandalay, footage shown by a media outlet showed.

In Myitkyina town in the north, which has seen confrontations in recent days, people laid flowers for the dead protesters while young people with banners drove around on motorbikes.

Crowds marched in the central towns of Monywa and Bagan and in Dawei and Myeik in the south, posted pictures showed.

"They aimed at the heads of unarmed civilians. They aimed at our future," a young protester in Mandalay told the crowd.

Military spokesman Zaw Min Tun, who is also the spokesman for the new military council, has not responded to attempts by Reuters to contact him for comment.

He told a news conference on Tuesday the army's actions were within the constitution and supported by most people, and he blamed protesters for instigating violence.

The more than two weeks of protests had been largely peaceful, unlike previous episodes of opposition during nearly half a century of direct military rule to 2011.

Members of ethnic minorities, poets and transport workers marched peacefully on Saturday in various places but tension escalated in Mandalay where police and soldiers confronted striking shipyard workers.

Some demonstrators fired catapults at police as they played cat and mouse. Police responded with tear gas and gunfire at the protesters, witnesses said.

Video clips on social media showed members of the security forces firing and witnesses said they found the spent cartridges of live rounds and rubber bullets.

Two people were shot and killed and 20 were wounded, said Ko Aung, a leader of a volunteer emergency service.

Police were not available for comment but the state-run Global New Light of Myanmar newspaper said the strikers sabotaged vessels and attacked police with sticks, knives and catapults. Eight policemen and several soldiers were injured, it said.

Reuters