The military launched an investigation into allegations that a missing soldier who vanished from her post at Fort Hood earlier this year was sexually harassed, officials said Thursday.

In a statement released by Fort Hood, officials said that the Army commander of Private First Class Vanessa Guillen’s regiment had appointed an investigative team to examine the allegations.

Guillen, 20, was last seen April 22 in the parking lot of her squadron headquarters at Fort Hood, roughly an hour north of Austin. Her car keys, barracks room key, identification card and wallet were found in the armory room where she was working the day she disappeared.

The announcement of the harassment probe came two days after Guillen’s mother, Gloria Guillen, told reporters that months had passed and “we know nothing, nothing, nothing. What’s happened? What happened on that base? Why did my daughter disappear?”

Vanessa’s sister, Mayra Guillen, told Dateline earlier this week that Vanessa had previously expressed to their mother that she felt unsafe at Fort Hood and that a sergeant had been sexually harassing her. Mayra said Vanessa never identified that person and never reported the incidents to the Army’s Sexual Harassment/Assault Response and Prevention program.

On Monday, military officials said investigators had uncovered no credible information that she had been sexually assaulted. Nor had they found evidence linking her case to another missing Fort Hood soldier, Gregory Wedel-Morales. Wedel-Morales was last seen on Aug. 19, 2019, driving in the city of Killeen, where Fort Hood is located.

The military has offered a $25,000 reward for information leading to Guillen’s whereabouts. The president of the League of United Latin American Citizens said Tuesday that the advocacy group is offering another $25,000.

The case has been publicized by actress Salma Hayek, who posted a photo of Guillen on her Instagram page last week with a message to her 15 million followers: “Bring back Vanessa…we won’t stop until you come back.”