The family of missing Fort Hood soldier Vanessa Guillén said Wednesday that her likely remains were found in a shallow grave near the Army installation in Texas, possibly bringing a months-long search for her to a tragic end.

Guillén, 20, was last seen on the morning of April 22 in the parking lot outside her regiment headquarters on the sprawling base outside Killeen.

Her disappearance, punctuated by allegations that she had been sexually harassed by a superior, sparked sadness and rage within her family and the Latino community, who said the Army’s investigative efforts after her disappearance moved too slowly.

“We lost a beautiful young soldier,” family attorney Natalie Khawam said at a news conference with Guillén’s family outside the Navy Memorial in Washington.

Killeen police encountered a suspect tied to Guillén’s disappearance early Wednesday. The fellow soldier “reportedly displayed a weapon and took his own life,” Army investigators said.

Guillén’s sisters Lupe and Mayra blasted Army leaders over Guillén’s death and the subsequent investigation. Sweat poured from Lupe Guillén’s face from behind a mask as she demanded inquires. She pulled the mask off, and her furious voice echoed across the marble ground.

“They didn’t keep my sister safe,” she said. “How can this happen at a military base?”

Mayra Guillén recounted a close encounter with the suspect during a visit to Fort Hood the day after her sister vanished.

“I met him not knowing he had something to do with it,” she said.

The family was flanked by U.S. Rep. Tulsi Gabbard (D-Hawaii). Gabbard and the family called for a congressional response and legislation that better protects service members facing sexual harassment and assault.

Gabbard, an officer in the Army National Guard, said she understands the importance of chain of command in resolving issues. “I also know the fear Vanessa must have felt” in seeking help, Gabbard said.

Army investigators found partial human remains near the Leon River, east of Fort Hood, said Chris Grey, a spokesman for the Army’s Criminal Investigation Command, the service’s equivalent of the FBI. The command has not confirmed that the remains found were Guillén’s, he said in a statement.

But evidence, including witness accounts and material recovered from the scene, made searchers “99.9 percent sure” that the remains were those of Guillén, said Tim Miller, director and founder of Texas EquuSearch, a nonprofit that assists in missing-person searches.

The remains were found a few feet from a pile of a burn mound that was searched June 20, Miller told The Washington Post on Wednesday.

Texas Rangers, detectives and cadaver dogs had not discovered the body until a return to the scene, he said.

“We were standing on top of her little body,” Miller said. Concrete had been poured over the remains, and subsequent rainstorms allowed the grave to settle into natural-looking terrain. Miller’s organization has recovered nearly 240 sets of human remains in two decades, he said, but the level of sophistication at the site was unprecedented.

“I never have seen anything like it,” he said.

Witness accounts helped lead to a breakthrough, he said. A man was seen struggling with a heavy-duty Pelican transport case in a car some time after Guillén’s disappearance, Miller said. A lid of a similar case was scorched but recovered at the burn site, he said.

On Tuesday, men building a fence near the site noticed a foul smell and walked over to investigate. They saw hair protruding from the ground, Miller said. He speculated some partial remains may have been dug up by animals.

The search was called off after the discovery, he said.

Guillén had complained to friends and family about being sexually harassed by a sergeant, according to her family and Khawam, but there is no record of any formal complaint. The Army said last week that the allegations did not produce viable leads.

Her family reported her missing hours after last communicating with her, and friends could not find her on the base. The family pressed the Army and federal lawmakers to pay attention to the case, enlisting the help of Rep. Sylvia Garcia (D-Tex.) and a Latino civil rights organization. Salma Hayek and other celebrities amplified the story.

“If they find my daughter dead, I will shut down this base,” her mother, Gloria Guillén, said during a news conference at Fort Hood last week.

Investigators found her car keys, barracks room key, Army identification card and wallet at the armory where she had worked the day before she disappeared. Several agencies, including more than 500 soldiers, used drones, helicopters and dogs to comb in and around Fort Hood, one of the biggest military bases in the country.

Army investigators confirmed Wednesday that another suspect has been arrested in the Guillén investigation — the estranged wife of a former Fort Hood soldier. She is being held at the Bell County Jail.

The Army did not release the names of either suspect.

Miller, who started EquuSearch years after his own daughter was abducted and killed, said his worst fears never materialized. Searchers worried that Guillén may have been set adrift in the Leon River, where the rushing waters would have carried her away.

“I think this is the best outcome there could have been,” he said. “I was worried Vanessa was going to be one of them that was never found.”

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