Nearly three-fourths of transgender and gender non-conforming Americans slain in the last three years were killed with a firearm, according to data published this month by the gun violence prevention advocacy group Everytown for Gun Safety. The data sheds grim new light on the role of guns in what's been called an epidemic of violence against transgender Americans, as advocates honor the victims with nationwide vigils Wednesday during the Transgender Day of Remembrance.

The data is available for the first time publicly via EveryStat for Gun Safety, the group's database detailing gun deaths in America. Everytown recently launched the database using data from the CDC and FBI, but independently tracks fatal gun violence against transgender people.

The data shows that 77 transgender and gender non-conforming Americans were killed since January 2017 — 74% of whom were killed with guns. Gun control advocates and LGBTQ rights advocates have both marked the deadly trend.

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"Transgender violence is a gun violence issue," said Sarah Burd-Sharps, director of research for Everytown for Gun Safety. "...These are critical issues for those of us in the gun violence prevention space to get on top of."

Mourners hold up a picture of slain transgender woman Denali Stuckey in North Charleston, South Carolina July 22 CBS affiliate WLTX-TV

The Human Rights Campaign, which also tracks anti-transgender violence, says 102 of the 157 transgender or gender non-conforming people were killed with guns since 2013. Someone motivated to harass or attack a transgender person based on hate poses a much higher threat with a firearm, said Sarah McBride, the group's national press secretary.

"One of the things we say is that hate is dangerous, but hate armed with a gun can be deadly," McBride said.

McBride said the LGBTQ community has begun "leaning in" to the gun control conversation, and the Human Rights Campaign began pushing for national gun control measures after the deadly 2016 Pulse nightclub massacre, McBride said.

The Human Rights Campaign says 22 transgender and gender non-conforming people were killed in 2019. Seventeen were killed with guns, according to EveryStat for GunSafety, and the majority — 20 — were black transgender women.

The Human Rights Campaign says black transgender women are at particular risk for violence because of a "toxic intersection of racism, sexism, transphobia and easy access to guns." Everytown's data shows that 82 percent of transgender gun homicide victims since January 2017 were black transgender women.

One of them was 29-year-old Denali Stuckey, who was found fatally shot along a North Charleston, South Carolina, roadway in July. Police said Stuckey had been on her way to a nightclub when a former neighbor, 34-year-old Dominick Maquis Archield, fired multiple shots at her "without any warning or provocation" before fleeing in a car. Archield later turned himself in and was charged with murder.

"She was always a nurturing person. A very sweet person. Any anniversary, any birthday, event, anything representing or celebrating you, she was always there," friend Mercdeas Arline told CBS affiliate WCSC-TV after her death. "I feel some type of way because I know she's not going to be here no more, and I won't be able to hear her laugh. And, she had this distinctive laugh that I swear keeps playing in my head."

The death has not been classified as a hate crime, though police have said they were still investigating a motive.

The Human Rights Campaign says that while some of the murders are directly motivated by hate, many transgender people struggle with discrimination that can push them out of jobs and homes, and a lack of access to social safety nets leaves them more vulnerable to violence — including intimate partner and sexual violence.

"While hate might not be an exact motivator for some of these crimes, it's very present in the circumstances that put transgender people at greater risk for violence," McBride said.

The most recent FBI data shows an increase in hate crimes targeting people because of their gender identity, from 131 offenses in 2017 to 184 in 2018. But advocates note that local law enforcement agencies voluntarily submit information about hate crimes to the federal government, and that number is likely significantly under-reported.

Xavier Persad, senior legislative counsel for the Human Rights Campaign, told CBS News this month that the data "reminds us of the importance of the work left to be done to protect LGBTQ people."

"We are talking about violence against people just because of who they are," Persad said.