The Army identified the remains of Guillen in Bell County, her family's lawyer said in a statement Sunday evening.
Lawyer Natalie Khawam said the U.S. Army Criminal Investigations Division told her that 20-year old Aaron David Robinson bludgeoned Guillen with a hammer at Fort Hood and later dismembered her and buried the remains in the woods.
Khawam said she was told the other soldier cleaned up the area where Guillen was killed, placed her body in a container and wheeled her out to his car.
SEE RELATED STORY: Remains of missing Fort Hood soldier Vanessa Guillen identified, lawyer says
Guillen's loved ones had mariachi music playing at the site of the new mural as they laid out candles, balloons and flowers in her memory.
"It obviously hurts knowing why this mural is going up, but it's really nice to see everybody appreciate who she was through the stories everyone is sharing and get an idea of who the person that was around us was," said one of her close friends.
WATCH: Meet the artists behind Vanessa Guillen's mural and what inspired them to do the design
The art is very symbolic of what her friends and family said she stood for. It displays the Mexico flag, portraying Guillen's Mexican-American heritage, and the American flag portrays the country she signed up to serve for.
The mural is located in her neighborhood at 8404 Park Terrace on the southeast side of Houston.
Mayor Sylvester Turner left flowers on Saturday at a memorial next to a different mural painted at a restaurant in southeast Houston
SEE RELATED STORY: Mayor Turner honors Vanessa Guillen with visit to mural
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