Police have confirmed they have received at least three reports of schoolchildren being approached by men.

Several schools in Watford, Rickmansworth, and Hemel Hempstead have written to parents warning their children to be vigilant and not speak to strangers.

Hertfordshire Constabulary says it is aware of the following incidents:

A 14-year-old girl was approached by a man at the junction of Windermere Close and Malmes Croft in Hemel Hempstead at around 8.10am on yesterday (Tuesday). It was reported the man offered the girl a lift but she declined and ran off.

The man did not try and grab or touch the child, police say.

He is described as Asian, smartly dresses and with a local accent. He was in a black two-door car. Anyone with any information on the incident is asked to call police via 101 quoting ISR 283 of October 2016.

Last Thursday, police received a report of a schoolgirl being approached by a man in Barton Way, Croxley Green at around 3.30pm. She was offered a lift but she declined and the driver moved off. He did not try and touch her or grab her.

This man has been described as white with a dark beard. He was wearing a dark blue hoody. His car was black and is believed to have been an Audi.

Anyone with any information is asked to call 101 quoting ISR 141 of October 12.

The day before, police were informed that two boys had been approached by a man in Dulwich Way, also in Croxley Green, at 8.15am. The man did not try to touch or grab the boys.

Following enquiries, a man has been identified and detained under the Mental Health Act.

Anyone aware of similar incidents that may not have been reported to police should contact the force via 101.