Army Sgt. 1st Class Kenneth Hardcastle, 31, was arrested on Monday amid allegations he was soliciting girls as young 10 for sex.

The Arapahoe County Sheriff’s Office in Colorado said Hardcastle was arrested on charges of internet sexual exploitation of a child and internet luring.

Announcing his arrest in a tweet on Tuesday, the sheriff’s office posted photos Hardcastle allegedly used to solicit girls and asked for parents to contact the office if their daughter has had contact with him.

“We worry there may be other victims. If he’s chatted with your daughter, call 720-874-8477,” the sheriff’s office said in the tweet.

According to police, Hardcastle used the dating website SeekingArrangement.com, where they say he attempted to contact girls for sex while identifying himself as “Colorado Batman.” The sheriff’s office also said investigators found the recruiter looked for girls on social media sites including Instagram, Snapchat and Facebook.

Hardcastle joined the Army in October 2008 and served as an air defense battle management system operator, according to Army Recruiting Command. He was assigned to recruiting duty in November 2015.

In August 2018, Hardcastle was removed from recruiting duty due to unrelated administrative actions and has not been in contact with potential recruits since then, said Kelli Bland, a spokeswoman for Army Recruiting Command.

“U.S. Army Recruiting Command takes any claims of inappropriate behavior very seriously and thoroughly reviews all allegations of misconduct," Bland said in a statement, "Recruiters are the face of the Army, and we expect them to serve honorably while representing the force.”

It’s not certain if Hardcastle has an attorney, and none is listed in court records, Shaun Clark, a court executive in Arapahoe County, said in news reports.