An activist poses with a photo of slain environmental rights activist Berta Cáceres during a march to mark International Women’s Day in Managua, Nicaragua, on March 8. (Oswaldo Rivas/Reuters)

When two gunmen left an award-winning environmentalist and indigenous leader dead in her home in rural Honduras this month, they also inadvertently left behind a witness.

Gustavo Castro, a Mexican colleague of Berta Cáceres’s and the only other person in the house at the time, was also shot, taking bullets in the ear and hand. After lying bleeding on the floor for a couple of hours pretending to be dead, Castro escaped by leaping over a gate and into a friend’s waiting car.

“He was very desperate, very distressed,” said Tomás Gómez, who picked Castro up that night. “He was afraid the assassins were going to come finish him off.”

Castro, now recovering in a house affiliated with the Mexican Embassy in the Honduran capital, Tegucigalpa, has become a central figure in the murder mystery that has shocked and captivated the country. Relatives and colleagues of Cáceres argue that the Honduran government is responsible for her death, either by failing to protect her after a string of threats or by ordering the killing — and Castro’s testimony could shed light on the culprits.

Soldiers guard the house where Cáceres was fatally shot March 3 in La Esperanza, Honduras. The indigenous activist was a respected environmentalist recognized for her advocacy. (Ricardo Castro/AFP/Getty Images)

So far, in an open letter, Castro has criticized the handling of the case, alleging that the “crime scene was altered,” but has not implicated anyone.

“The gunmen who killed Berta and tried to kill me remain unpunished as the government seeks to undermine the memory of Berta,” he wrote.

President Juan Orlando Her­nández has called Cáceres’s killing a “crime against Honduras” and promised a thorough investigation.

But colleagues and relatives of Cáceres have raised questions about the possible role of Honduran soldiers and police in her March 3 death. They cite what they call a pattern of intimidation and abuse by security forces, including a national police unit called Los Tigres, which was set up by U.S. Special Forces soldiers over the past two years and receives funding and training from the United States. Before she died, Cáceres warned U.S. visitors about Los Tigres, describing the unit as a “repressive” force in her region of western Honduras.

The U.S. Embassy in Honduras has looked into all allegations of abuse by Tigres commandos and “to date, we have seen no credible evidence to substantiate” them, according to an embassy official who was not authorized to speak publicly.

Last week, a colleague of Cáceres’s, Nelson García, was shot to death after he returned home from helping indigenous people evicted from their residences by police.

“This is an incredibly important test case” for Honduran institutions, said Eric Olson, a Central America expert at the Woodrow Wilson Center in Washington who knew Cáceres. “She was very dynamic and clearly very committed and fighting this good fight trying to protect indigenous people.”

Friends and supporters gather around Cáceres’s coffin during a Mass outside the Virgen de Lourdes church in La Esperanza on March 5. (Jorge Cabrera/Reuters)

Cáceres, a mother of four who lived in the western city of La Esperanza, was a member of the indigenous Lenca people who spent her adult life battling to preserve the environment and indigenous culture in the area. In 1993, she co-founded the Civic Council of Popular and Indigenous Organizations of Honduras, known as COPINH, to oppose logging in Lenca territory.

In recent years, she and her organization had opposed mining, dam and hotel projects, most notably targeting construction of the Agua Zarca hydroelectric dam — an effort for which she was awarded the prestigious Goldman Environmental Prize last year.

The Honduran company Desarrollos Energéticos S.A., known as DESA, has continued the project, even as its partner, the Chinese company Sinohydro, backed out. A statement on the Agua Zarca dam website denies any connection between the project and Cáceres’s death.

Since 2013, as protests intensified, Cáceres had received anonymous death threats, said her daughter, Berta Isabel Zúñiga Cáceres. In July that year, during a demonstration against the dam, soldiers based at DESA’s offices shot into the crowd and killed Tomás García, another COPINH member.

Last month, a delegation from Witness for Peace, a nonprofit group focusing on peace and justice in Latin America, met with Cáceres and other COPINH leaders and toured the area around the dam site. Cáceres told the visitors that dam opponents’ names were on hit lists. “Any member of COPINH is in danger,” she said, according to notes from the meetings.

Colette Knudsen, a nurse practitioner on the trip, said Cáceres and others were photographed by DESA guards when they went down to a river to swim. Knudsen said that Honduran police followed their vehicle as they left the area.

“We experienced the psychological terror, basically,” she said.

In a meeting with Witness for Peace on Feb. 18, Cáceres said that the Tigres commandos “have been a hostile and aggressive presence,” according to a transcript of her remarks. The unit, which has 283 members, has generated controversy before: In 2014, the Tigres arrested cocaine traffickers but allegedly stole more than $1 million. Dozens of them were fired, and 11 were arrested.

Cáceres said that the United States was funding these “repressive units.”

“So in a way, the government of the United States and the army of the United States is responsible for the violation of the rights of the Lenca people,” Cáceres said.

The U.S. official said embassy personnel have met with Cáceres’s relatives, COPINH members and other supporters since her death to hear their concerns but added that the embassy has “no credible evidence that supports the allegations of Tigres involvement in acts of violence, threats or intimidation against members of COPINH.”

In late February, Cáceres pressed police to capture a suspect wanted in the slaying of another COPINH member, and the Tigres found and arrested the person, which Cáceres applauded, the official said.

The suspicion that has fallen on the security forces in connection with Cáceres’s death has emerged in the absence of other suspects or hard evidence. The Honduran attorney general said that at least 50 people are working on the investigation, but relatives and colleagues see Cáceres’s killing as a political assassination and don’t believe authorities will conduct an impartial investigation. Her family’s request for an independent autopsy has so far been rejected, according to her brother Gustavo Cáceres.

“You have to say that the assassination of my mom was due to her intense fight against this hydroelectric project,” Cáceres’s daughter, Zúñiga, said in an interview. “If they’ve killed her, someone so well-known, they can kill anyone.”

Castro, from the Mexican city of San Cristobal de las Casas, had known Cáceres for several years in environmental and social-
justice circles and had gone to her house to take part in energy conservation workshops. After the shooting, the house was swarmed by officials, according to Cáceres’s family.

Castro was taken into police custody and interrogated for two days, with little food and no sleep, according to his brother, Oscar Castro. Gustavo Castro tried to leave Honduras but was blocked at the airport, and a judge has ordered that he stay in the country for 30 days, a ruling his attorneys are contesting.

“They are putting him at more risk” by keeping him in Honduras, Oscar Castro said by phone from Tegucigalpa. “This is causing a lot of stress.”

This story has been updated to correct that opponents of the dam, rather than supporters, were allegedly put on hit lists.

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