FILE - Demonstrators protest against the military coup and demand the release of elected leader Aung San Suu Kyi.
FILE - Demonstrators protest against the military coup and demand the release of elected leader Aung San Suu Kyi, in Yangon, Myanmar, Feb. 6, 2021.

The United Nations high commissioner for human rights said Friday that violence in Myanmar is rising, deepening the crisis that began with the February 1 coup that toppled the elected government of Aung San Suu Kyi.

"In just over four months, Myanmar has gone from being a fragile democracy to a human rights catastrophe," Michelle Bachelet said in a statement in Geneva, Switzerland. 

Bachelet put the blame on the military leadership, known as the Tatmadaw, saying it was "singularly responsible" for the crisis and “must be held to account.”

“State security forces have continued to use heavy weaponry, including air strikes, against armed groups and against civilians and civilian objects, including Christian churches,” she said. 

“The international community needs to unify in its demand that the Tatmadaw cease the outrageous use of heavy artillery against civilians and civilian objects,” Bachelet said.

Bachelet's office said there are credible reports that at least 860 people have been killed by security forces since February 1, and more than 4,800 people, including opponents of the junta, activists of civil society and journalists, have been arbitrarily detained.

The U.N. human rights chief will brief the Human Rights Council on the situation in Myanmar during its next session in July, the office said.