The burned remains of 17-year-old Ally Lee Steinfeld were found last week in a bag in a rural southern Missouri chicken coop. Authorities said the transgender teen's eyes had been gouged out and she had been stabbed repeatedly in the genitals.

Three people — Briana Calderas, 24, Andrew Vrba, 18, and Isis Schauer, 18 — have been charged with first-degree murder and other counts. A fourth suspect, 25-year-old James Grigsby, has been charged with abandonment of a corpse and tampering with evidence.

Steinfeld's remains were found in the town of Cabool, near the mobile home of Calderas, with whom Steinfeld was living.

(L-R) Briana Calderas, Isis Schauer and Andrew Vrba. Photos courtesy of Texas County Sheriff's Department. Texas County Sheriff's Department

As questions swirl about why Steinfeld was killed in such a ghastly manner, authorities are not saying what led to her murder. However, they have dismissed the possibility her death was a hate crime. Both Sheriff James Sigman and prosecutor Parke Stevens Jr. insist the crime was not motivated by Steinfeld's gender identity.

"I would say murder in the first-degree is all that matters," Stevens said. "That is a hate crime in itself."

Yet the killing has drawn the attention of LGBTQ advocates and others across the U.S. who believe Steinfeld was targeted for her gender identity despite the assertions of the sheriff and prosecutor.

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"This violence, often motivated by hatred, must come to an end," said Chris Sgro, a spokesperson for the Human Rights Campaign, who said Steinfeld was the 21st transgender person killed this year in the U.S. "We will continue to mourn Ally and fight back against transphobia and anti-trans violence."

Beverly Tillery, executive director of the Anti-Violence Project in New York City, said Steinfeld's death is part of a rising epidemic of violence against transgender people in the U.S.

“We have well exceeded the number of homicides that we reported in all of last year, and of course we still have a lot more of the year to go," she said. "These kinds of attacks are increasing unfortunately. This one is particularly brutal. We are seeing this increase, an increase in this climate of hate against LGBT people, specifically trans people. We have been calling for people to really pay attention to this crisis.”

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Ally Lee Steinfeld's mother, Amber Steinfeld, still refers to her child — who was assigned male at birth — by her given name, but said the teen identified as female to family and to friends on social media. She said her child was "loving and kind-hearted."

Steinfeld was engaged to a woman until they broke up in August, Amber Steinfeld said, and soon after began dating Calderas. She said her daughter and the two 18-year-old suspects were all living at Calderas' mobile home. She said Steinfeld was upbeat before she disappeared, telling relatives that she loved them and was happy.

In May, Steinfeld posted on Instagram that she was coming out and was "mtf," or male-to-female. In a posting on June 13, Steinfeld referred to herself as "Trans male to female and I am mostly lesbian but pansexual." In another post that same day, she wrote, "I am proud to be me I am proud to be trans I am beautiful I don't care what people think."

Vrba told investigators he initially tried to poison Steinfeld, then described how he stabbed Steinfeld in the living room of Calderas' mobile home, Deputy Rowdy Douglas wrote in a probable cause statement. The female suspects said Vrba bragged to them about how he gouged Steinfeld's eyes and stabbed Steinfeld in the genitals, Douglas wrote. The probable cause statement does not offer any motive.

Authorities say the three suspects burned Steinfeld's body, placed some of the bones into a garbage bag and put the bag in the chicken coop. Calderas admitted helping burn the body and led authorities to the knife used in the killing, Douglas wrote.

An attorney for the three suspects, Michael Jacobs, said Tuesday that it was still too early to comment.

Linda Camara, 61, a friend of Steinfeld's family, was struck by the gruesome nature of the killing.

"People kill each other, which is bad, but to do it that way, that's something you see in movies," Camara said. "And the three people who did this, they were kids, too."

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