A Nicaraguan-American dual national who died in a prison disturbance in Nicaragua served in the U.S. Navy and was a staunch opponent of the government of President Daniel Ortega, his cousin said Saturday.

Eddy Montes Praslin, 56, was shot dead Thursday at La Modelo prison outside the capital of Managua. Hundreds of Nicaraguans have been jailed over the past year after protesting against the government.

His cousin Marvin Montes told The Associated Press that Montes Praslin moved to the U.S. when he was 13 years old, went to school in California and served in the Navy.

He said Montes Praslin traveled back and forth between the two countries, establishing himself more permanently in Nicaragua since 2006. Montes Praslin at one point studied medicine, and he received a law degree from a Nicaraguan university in 2018, his cousin said.

At least 17 others who had been arrested for apparently participating in anti-government protests were wounded in the prison disturbance. The government said prisoners rushed at guards.

Marvin Montes said his cousin was jailed in October after complaining to police that pro-government activists had occupied several acres of his property in Matagalpa, a city in northern Nicaragua.

The attorney general's office accused him of terrorism, aggravated robbery, obstruction of public services and attacking the mayor's office in Matagalpa.

The Nicaraguan Center for Human Rights represented Montes while he was in prison.

"We have an account of the persecution that he suffered over his property going back more than two years," said Vilma Núñez, president of the human rights center.

Núñez said that in addition to the property dispute, Montes had offered to testify as a witness to a murder that he said was committed by government agents.

"Eddy was there and saw everything," said cousin Montes.

Attorney Yonarqui Martínez, who represents more than 70 political prisoners, said via Twitter that there is "proof" that Montes Praslin was shot in the back rather than during a tussle. It's unclear whether an autopsy will be performed.

Fellow inmates looked up to Montes Praslin, calling him "pastor" because he led religious gatherings and even "father" because he was much older than the many students who are in jail.

Student-led protests against social security reforms began in April 2018 and grew in scope to demand Ortega's exit from office and early elections. The demonstrations were put down forcibly by security forces and armed, pro-government militias, with at least 325 people killed in the crackdown, more than 2,000 wounded and over 52,000 who fled the country, according to the Inter-American Commission on Human Rights.

Daughter Eddy Jafet Montes, who lives in California, told a Nicaraguan media outlet that she would travel to Nicaragua for the funeral, but with trepidation.

"If they threw my father in jail under any excuse, I feel they could do the same to us," she said.

The funeral is expected to take place on Sunday, according to Marvin Montes.

U.S. Ambassador Kevin Sullivan expressed sadness at Montes Praslin's death and said he met with family members Friday to convey the U.S. government's condolences.

"They deserve a comprehensive and credible account of this unjustifiable use of lethal force against an unarmed political prisoner," Sullivan said via Twitter. A U.S. State Department official reiterated the government's call for the release of all political prisoners.