- US Army Spc. Aaron Robinson, who had been a person of interest in the ongoing investigation, previously fled Ft. Hood and killed himself when law enforcement officials approached him.
- Army investigators reportedly found Robinson used a hammer to attack Guillen, causing "her blood to be splashed all over the armory room," according to the attorney.
- Robinson allegedly used his girlfriend, who was married to somone else, to assist in burying Guillen's remains after they attempted to burn her body.
- Partial remains that were discovered near Ft. Hood have not yet been identified.
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The missing 20-year-old US Army soldier was allegedly killed by a fellow soldier the same day she disappeared, a family attorney said in a statement to Army Times .
Attorney Natalie Khawam was reportedly briefed by Army investigators, who said US Army Spc. Vanessa Guillen was attacked by Spc. Aaron Robinson, another soldier who was not within her chain of command, in an armory room at Fort Hood, Texas.
Robinson was said to have allegedly used a hammer to attack Guillen, causing "her blood to be splashed all over the armory room," Khawam told Army Times.
Armory rooms in the US Army are used to securely store a variety of military weapons when not in use, and are usually orderly.
Robinson then enlisted his girlfriend, who was married to someone else, to assist in burying Guillen's remains after they attempted to burn her body, Khawam said, adding that she was eventually dismembered with a machete.
Robinson, who left Ft. Hood, became a person of interest in the investigation on Tuesday. He shot and killed himself when law enforcement officials approached him after tracking him down.
Robinson's girlfriend was found and is currently in jail. It was unclear whether charges have been filed.
Guillen previously complained of sexual harassment from one of her superiors, according to her family members. Khawam said Guillen "was afraid" to report the incident "because the sexual harassment was coming from her superiors."
"So her concern was the retaliation, being blackballed," the attorney said in a press conference. "We believe the person that killed her is that person that sexually harassed her."
A separate investigation into the sexual harassment allegation, in addition to the investigation into Guillen's disappearance, has been launched. As of Thursday, Army investigators said they did not find a connection between the sexual harassment claim and her disappearance. They added that there was not yet credible evidence that she was sexually harassed.
On Tuesday, partial human remains were found in an area of Texas being investigated in the search for Guillen. Investigators are still trying to identify the remains, Ft. Hood officials said during a press conference on Thursday.
Guillen, a Houston native, was last seen at Ft. Hood on April 22. Following her disappearance, investigators found the keys to her car and room along with other identification cards in the armory where she worked on that same day. More than 300 people were interviewed during the investigation, which spanned multiple law-enforcement agencies and nonprofit groups.
Ft. Hood officials have been criticized for not widening its search for Guillen after her disappearance.
"They lied to our face," Guillen's sister, Lupe, said during a press conference. "They didn't keep my sister safe. My sister is a human too."