The UN Office of the High Commissioner for Human Rights (OHCHR) issued a press release on Friday warning of the possibility of an imminent attack by the Myanmar military against its opponents.

In the release, OHCHR noted that there had been a build-up of heavy weapons and troops by the Tatmadaw, the Myanmar military, in several townships across three regions of the country in recent days. Two high-level commanders have also been dispatched to the areas, and internet service has been shut down. OHCHR has documented intensified attacks by the Tatmadaw in these areas over the past month, including killings of civilians, the raiding of villages, and burning of homes, all of which are attempts to ferret out armed resistance and to act as reprisals against villages believed to be sympathetic to the resistance.

The warning comes nearly two weeks after High Commissioner Michelle Bachelet called upon all armed actors in the country to work to prevent a human rights catastrophe. She had also called upon the international community to take action with regard to the February coup that unseated the elected government and placed the military in charge. Friday’s press briefing similarly called upon other nations “to speak with one voice, to prevent the commission of further serious human rights violations against the people of Myanmar.”

Over 1100 people have been killed by security forces since the coup began.