(CNN) A human rights watch group is accusing Nicaraguan authorities of using excessive force, threats and torture against demonstrators since protests began in the country last month.

In a preliminary report, the Inter-American Commission on Human Rights says at least 76 people have been killed and 868 injured in anti-government protests.

According to the Nicaraguan government, the death toll is 13. CNN has reached out to authorities for comment and has not yet received a response.

The rights group, known as IACHR, is calling on Nicaraguan officials to ban the use of lethal force against protesters after it found evidence that police "used firearms, rubber bullet guns and tear gas indiscriminately to dissolve protests and demonstrations."

"Potentially lethal force cannot be used to maintain or restore public order. Only the protection of life and physical integrity before imminent threats can be a legitimate objective to use such force," the IACHR said.

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