Myanmar has been in turmoil since a February 1 coup ousted civilian leader Aung San Suu Kyi and derailed the country's experiment with democracy.

Business consultants Matthew O'Kane and Christa Avery, a dual Canadian-Australian citizen, tried to leave the country on a relief flight in late March but were barred from departing and placed under house arrest.

"I am of course incredibly relieved to have been released and to be on my way home with my husband Matt," Avery said in a statement.

"Even though I knew that I had done nothing wrong it was very stressful being held under house arrest for two weeks, not knowing what was going to be the outcome of the questioning."

The couple said they were incredibly sad to leave Myanmar, which was their home for eight years, and hope the country stabilises soon.

A spokesperson for Canberra's foreign affairs department said Australian diplomats had "provided support for their departure from Yangon on 4 April."

The couple ran a bespoke consultancy business in Yangon.

A third Australian, economist Sean Turnell, was arrested a week after the putsch and remains in custody.

The university professor and advisor to Suu Kyi was the first foreign national arrested following the coup.

He has been charged with a violation of state secret laws, along with Suu Kyi late last month.

More than 2,500 people have been detained since the coup, according to local monitoring group Assistance Association for Political Prisoners. It also recorded the death toll as 564 as of Sunday, as security forces continue to use lethal force against protesters.

Despite six weekend deaths, demonstrators returned to the streets Monday in Mandalay, Yangon, Bago, a small town in Kachin state and Pale township in Sagaing region, according to social media posts.

- Ceasefire suspended -

Ten of Myanmar's major ethnic armed groups voiced support for the anti-coup movement over the weekend, stoking concerns that their involvement could ignite a broader conflict.

Following the groups' online meeting, Restoration Council of Shan State chair General Yawd Serk told AFP the 2015 nationwide ceasefire agreement effectively stopped when the military staged the coup.

"The peace process has been violated by the military. This is not a good thing. What we are saying is that at the moment, the military's hands are bloodstained," he told AFP on Monday.

"We are not saying the national ceasefire agreement is broken - it is suspended."

Anti-coup protesters are set to hold a co-ordinated round of applause for ethnic groups siding with the pro-democracy movement later Monday.

Meanwhile, two Myanmar soldiers were killed in a bomb explosion in Tamu near the Myanmar-Indian border during a clash between security forces and protesters Sunday.

"It was like a war as they attacked each other in the town. We could hear them shooting each other. We even could hear bomb attacks too sometimes. We could hear a lot of guns fighting. No one dared to go out as they were fighting," a women's rights activist told AFP.