Nicaragua announced Wednesday that it was expelling international experts investigating allegations of human rights abuses by security forces during anti-government protests earlier this year in which demonstrators had demanded President Daniel Ortega leave office.

The move came a day before the experts were scheduled to hold a news conference in the country to present their findings on the unrest that began in April. More than 320 people were killed in the upheaval, according to non-governmental groups that have also denounced numerous cases of alleged torture, arbitrary detentions and persecution of government opponents.

A Foreign Ministry letter to the secretary-general of the Organization of American States, Luis Almagro, alleged that regional bodies had acted "irresponsibly in the criminal, interventionist escalation, promoting terrorist actions of political, economic and military order."

It cited previous comments by Almagro calling on the international community to put pressure on "the dictatorship that is being installed in Nicaragua," and accused the secretary-general of "lies and slander."

The letter also said the Special Monitoring Mechanism for Nicaragua, or Meseni, and the Interdisciplinary Group of Independent Experts, or GIEI, violated an agreement signed in June opening the door for them to investigate killings in the country.

Both are arms of the OAS, which said in a statement that the government's decision "further places Nicaragua into the terrain of authoritarianism. Expelling researchers and institutional defenders is characteristic of those who do not want to see justice done and perpetuate impunity."

Ortega's government says it has been the victim of an attempted "coup," and the ministry criticized those organizations for not reflecting that claim in their reports.

The letter Wednesday formally announced the suspension of the visits by the rights monitors, effective the same day. The experts were summoned to the Foreign Ministry and accused of spreading false information.

"They asked us to leave the country immediately and we hope that our headquarters in Washington will take care of the logistics for us to go," delegate coordinator Ana Maria Tello said at a news conference. She added that rights monitors would continue to follow the situation in Nicaragua from outside the country.

Meseni's job in the country was to follow up on recommendations from the Inter-American Commission that, among other things, urged Ortega's government to cease repression of civilians, disband pro-government paramilitary groups and guarantee respect for media freedoms.

The protests fizzled after a harsh crackdown by security forces and armed, pro-government civilian militias, and since then Ortega has reconsolidated power and methodically pursued perceived enemies. Just in the last week, Nicaraguan police raided the offices of five non-governmental organizations and the independent media outlet Confidencial, carrying off documents and computers.

The Center for Justice and International Law, a regional NGO, criticized the expulsions of the experts just a day before the presentation of the report.

The experts "faced a government that blocked and boycotted their work, by closing down all spaces for dialogue and monitoring and by denying them access to essential information in fulfilling their mandates," the center said.