THOUSANDS of pupils have been told not to walk to school alone after a ‘suspicious man’ approached children.

Oxfordshire’s biggest school, 2,129-pupil Lord Williams’s School in Thame, issued the warning on Friday after reports of a pierced man speaking to a schoolgirl.

It was the third Oxfordshire school to send a safety warning to parents and children last week, after another suspicious man of a different description was seen loitering near Oxford schools.

Writing on the Thames Valley Police South and Vale Facebook page, officers said a ‘male acting suspiciously approached a female student on her way to school.’

It happened at about 9.30am on Friday, on the Thame Park Road junction of Chowns Close in Thame.

The man was described as white, in his 40s, and was wearing black jogging bottoms with ‘paint and mud on,’ police said.

He had a large piercing in his left ear along with smaller studs, and had short ginger or brown hair.

READ AGAIN: Suspicious man approaches schoolgirl in Thame

He was described as ‘very slim’ and wore a black coat.

A force spokesman told the Oxford Mail: "Thames Valley Police is investigating the offence and would encourage anyone with information to contact our enquiry centre on 101 or visit our website.

"We are carrying out an investigation, including house-to-house enquiries and obtaining and reviewing CCTV.

"We are liaising with and supporting the victim."

He did not state whether or not the man had said or done anything to the girl.

Lord Williams’s sent an email to parents on Friday afternoon, which was shared via a screen shot on the Spotted: Thame Facebook page.

The message, signed off by the school’s new headteacher Jon Ryder, stated: “Following advice from the police, we want to alert you that we have received reports of a suspicious man approaching students on the way to and from school in the area around Lower School.

“We will advise students to walk to and from school in pairs or groups and would ask you to reinforce safety messages with your children.

“The police are currently investigating these reports - if you have any further information please contact 101.”

One parent, commenting on the police post on Saturday, said officers had been told of two such reports between Thursday and Friday.

She added: “Please can the police show increased visibility outside the school - children said they saw no police around the area.”

Last week, St Gregory the Great Catholic School and Oxford Spires Academy in East Oxford warned parents about a ‘suspicious man’ seen in Barracks Lane at the end of the day.

READ AGAIN: 'Suspicious man' seen hanging around Oxford schools

The man was described as ‘Afro-Caribbean with short hair and stocky build.'

St Greg’s told parents that police will ‘make their presence known in the area’ and the school also said parents should deter their children from walking home alone.

Oxford Spires was contacted for further information but said the matter was with police, while Thames Valley Police could not provide further information without times and exact locations of the sightings, or a crime reference number.

In response to that article, one Oxford Mail reader said her daughter was ‘followed’ by a suspicious man in Headington as she walked home from school on Wednesday.

She said: “My daughter said she was followed in Headington after separating from her friends.

“She called me and stayed talking to me on the phone until I got there.

“She quickly went into a shop with CCTV but she said the guy turned back looking for her. I was a few minutes away thankfully.”

The mother said this happened on London Road, between Windmill and Kennet Road.

Thames Valley Police has been asked for more information about the Thame reports.

Police advised anyone with information about the man to call 101, quoting reference 43190324029.