A Colorado man is in jail after attempting to kidnap a boy at Black Forest Hills Elementary School in Aurora, police say.

Solomon Galligan, 33, walked onto school property and approached several children on Friday afternoon and tried to grab a boy before leaving the area, an Aurora police spokesman told CBS News Colorado on Sunday.

It wasn’t immediately clear what prompted him to leave, but Aurora police say officers found a man matching the description of the one reported and arrested Galligan.

A request for an arrest report was pending Sunday.

Galligan has been charged with one count of attempted kidnapping and is being held in the Arapahoe County Jail on a $25,000 bond. He’s due back in court Monday morning.

The nature of Galligan’s previous sex crime wasn’t immediately clear as he did not appear in the state’s sex offender registry, but court records show a 2012 conviction in Jefferson County for failing to register as a sex offender.

A phone call to parents on Friday afternoon said that an unidentified man entered school property, “engaged” students and then left. The call indicated that recess was ended early and the students were brought inside as security and police investigated the incident and that parents could pick up their students early if they wanted to. That call went out at 2:16 p.m., according to a school district spokesperson.

Black Forest Hills Elementary Principal Amanda Replogle alerted parents of the incident in an email that was sent after school got out on Friday informing them that the incident occurred during one of the recess hours and that school staff met and will continue to meet to discuss what happened.

“Today after dismissal, we held a meeting with staff and district security, and I asked staff to maintain continued diligence around safety precautions,” her email said, in part. “On Monday, I will convene our School Safety Team to review security protocols and procedures.”

Then at 3 p.m. on Sunday, the school district sent out an email to Black Forest Hills Elementary parents informing them that the person they mentioned in the earlier messages has since been arrested and charged with attempted kidnapping.

“We share this information to keep you informed and offer some important safety tips,” the email says. “Please remind your child to be watchful as they are walking to and from school, to walk in pairs or with friends, and to avoid talking with and to never accept a ride from strangers. Also, remind students to report anything suspicious to police or a trusted adult at school.”