Local outlets in Puerto Rico on Wednesday reported the murders of two transgender women.

Serena Angelique Velázquez, 32, and Layla Pelaez, 21, were found in a car that had been set on fire. They had been shot, Puerto Rico daily El Nuevo Dia reported. Authorities found the car with the women inside under a bridge in the municipality of Humacao on the island's southeast coast.

Detectives told other outlets that they were attempting to identify a motive.

A coalition of LGBT advocacy groups known as El Comité Amplio para la Búsqueda de la Equidad (CABE) called on authorities to investigate the murders as a hate crime.

“We urge the police to adequately, immediately and with sensitivity investigate these vile and atrocious murders of Serena Angelique Velázquez and Layla Pelaez,” the group said in a statement.

In a blog post, the Human Rights Campaign (HRC) said that it was “deeply saddened” to learn of the murders.

“Transgender and gender non-conforming people, especially women of color, are too often the victims of a toxic mix of transphobia, racism, and misogyny,” said Tori Cooper, HRC director of community engagement for the Transgender Justice Initiative. “People and policy must work together to protect our lives and our well-being. HRC stands in solidarity with all who knew and loved them."

HRC said that of the eight transgender or gender non-conforming murders in the United States this year, four have been in Puerto Rico.