"The true orchestrators of these crimes mostly escape investigation, but available information suggests that large landowners, business interests, political actors and agents of organized crime are often behind the violence," the report said.

The report said that it was difficult to find information about who committed the killings but that at least 10 were attributable to paramilitary groups, eight to police, five to private security guards and three others to military forces.

Over the last 12 years, the overwhelming number of activists killed were from Latin American countries, with just Brazil accounting for 477 deaths from 2002 to 2014, according to Global Witness.

A total of 116 activists were killed around the world in 2014, with 87 of them killed in Latin American countries, according to the report, "How Many More?" Brazil had the most deaths, with 29, followed by Colombia with 25.

Latin America remained the most dangerous place for environmental and land rights activists last year — accounting for three-quarters of killings related to opposition to hydropower projects, mining, agribusiness and logging — according to a report released Monday by U.K.-based rights group Global Witness.

Honduras — where 12 environmental and land rights activists were killed last year — had the highest per capita death rate of any country surveyed in the report for the fifth straight year. There were 111 killings reported there from 2002 to 2014.

"Recent regressive laws, collusion between powerful political and business interests and a climate of near total impunity have increased violence related to a surge in destructive agriculture, mining and dam projects in recent years," the report said of Honduras.

The report praised Honduran indigenous activist Berta Caceres and said she has faced repeated threats for her work, including her fight against the Agua Zarca hydroelectric dam on the Gualcarque River.

She was set to receive the 2015 Goldman Environmental Prize for grass-roots environmental activism on Monday in San Francisco. The group said three of her colleagues have been killed while opposing the project.

Heightened dangers faced by environmental activists in Honduras are likely to be raised next month at the Geneva-based United Nations Human Rights Council when the country's rights record comes under review, Reuters reported.

Also noted in the report is that 47 people — 40 percent of the activists who were killed — were indigenous. In Colombia, indigenous people accounted for 15 of the 25 environmental and land rights activists who were killed last year.

The authors also said that even as the report went to press on April 5, an indigenous leader "fighting illegal logging in his community" was found murdered in northern Honduras. A few days later, Fernando Salazar, who had been advocating for the rights of his indigenous community in Colombia "in the face of widespread illegal mining" was killed outside his home, the report said.

Global Witness called on governments to do more to ensure the safety of activists and to bring perpetrators — of killings and environmental abuses — to justice.

"Environmental defenders are fighting to protect our climate against ever-increasing odds," said Billy Kyte, a campaigner at Global Witness.

"We need to start holding governments and companies to account for the rising death toll on our environmental frontiers,” he said. “The secrecy around how natural resource deals are made fuels violence and must end. It's time for the international community to stand up and take notice."

Al Jazeera and wire services