(CNN)Human remains found in a shallow in Texas grave were positively identified as Army Spc. Vanessa Guillen on Sunday, according to Guillen family attorney Natalie Khawam.
Guillen, 20, had been missing since April and was last seen in the parking lot of her barracks at Food Hood on April 22, according to the US Army Criminal Investigation Command (CID). Her remains were found June 30.
The main suspect in disappearance was identified by officials on Thursday as Spc. Aaron David Robinson, who shot himself Wednesday after being confronted by investigators, according to the Killeen Police Department.
Khawam said the family told her that Guillen had planned to file a harassment complaint against Robinson the day after she was killed, and that they believe Robinson became enraged when she told him that.
Fort Hood officials said they were not aware of reports of sexual harassment involving Robinson but the investigation was ongoing.
Khawam said investigators told the family that Robinson called a woman he was involved with to help him dispose of Guillen's body after moving it outside the base.
A woman identified as Cecily Anne Aguilar was arrested by Texas Rangers in connection with Guillen's disappearance. She is in Bell County Jail awaiting civilian authorities to press charges, CID said.