Nearly two years after Myanmar's military coup, the UN rights chief warned Friday that the country had plunged into catastrophe, calling for the military to be brought under civilian oversight.

Since the coup that toppled Aung San Suu Kyi's civilian government on February 1, 2021, Myanmar has "by nearly every feasible measurement, and in every area of human rights... profoundly regressed," Volker Turk said in a statement.

"Despite clear legal obligations for the military to protect civilians in the conduct of hostilities, there has been consistent disregard for the related rules of international law," he said.

"Far from being spared, civilians have been the actual targets of attacks -- victims of targeted and indiscriminate artillery barrages and air strikes, extrajudicial executions, the use of torture, and the burning of whole villages."

The UN rights office said at least 2,890 people had died at the hands of the military and its allies since the coup, pointing to credible sources.

Of those, "at least 767 were initially taken into custody", it said, adding that "this is almost certainly an underestimation of the number of civilians killed as a result of military action".

The military has also imprisoned the democratically elected leadership of the country, and more than 16,000 others, the rights office said.

Another 1.2 million people have meanwhile become internally displaced since the coup, while more than 70,000 have left the country.

They have joined more than one million others who have fled persecution in Myanmar over the past decades, including most of the country's Rohingya Muslim population.

"There must be a way out of this catastrophic situation, which sees only deepening human suffering and rights violations on a daily basis," Turk said.

He decried that the junta had treated a plan agreed with the Association of Southeast Asian Nations (ASEAN), aimed at quelling the bloodshed and allowing humanitarian access, "with disdain".

Instead, "violence has spiralled out of control and humanitarian access has been severely restricted", he said.

Turk insisted that "those responsible for the daily attacks against civilians and the human rights violations must be held accountable".

"How can a military that purports to defend the country have brought their own people -- from all parts of Myanmar's rich and diverse society -- to such a point of desperation?" he asked.

"The military needs to be brought under real, effective civilian oversight."