A man was arrested in Watford on Thursday, February 27, on suspicion of stalking an 11-year-old girl.
The man, from Watford, is currently in police custody.
The incident happened in Vicarage Road, between the hospital site and the football stadium, between 8.30am and 8.40am on the morning of February 26.
A man reportedly attempted to engage the girl in conversation before touching her shoulder.
Other members of the public saw what happened and asked him to stop before ensuring the girl arrived at school safely.
Her parents were telephoned, and the police were informed. An investigation was launched, and detectives are in the process of gathering statements from the victim and witnesses.
Watford chief inspector Matt Phillips said: “I completely understand that news of this is going to cause deep concern within the community but thanks to the quick actions of the public, the victim’s school and the police, a man is currently in custody.
“Detectives are supporting the victim and her family, and several lines of enquiry are currently underway.
“Incidents of this nature are very rare in Watford and Hertfordshire as a whole, and I can confirm that we are treating this as an isolated case.
“In light of yesterday’s incident, I would encourage parents and carers to discuss personal safety with their children and ensure they know that it is appropriate to dial 999 if they believe they are being followed by a stranger.
“If you witnessed what happened and have not yet spoken to police, please contact us quoting reference ISR 163 of February 26.
“We would ask that the public refrains from discussing the incident on social media.”