Schools are warning parents an online suicide game may be making its way into children’s YouTube videos such as Peppa Pig.

A number of institutions across the country have posted alerts on their social media pages, telling parents of the “highly inappropriate” videos.

According to the Parentzone website, the Momo Challenge is played over WhatsApp, with the Momo character asking would-be participants to contact “her” and carry out a series of challenges — the final one being suicide.

The Momo character features a disfigured face with stretched features attached to a bird’s body.

YouTube said it had not received any evidence of the challenge on its site.

But Haslingden Primary School in Rossendale, near Blackburn, has posted a warning to parents on its Facebook page.

It said: “We have become increasingly aware of highly inappropriate videos circulating online and are being viewed by children across the school.

“These video clips are appearing on many social media sites and YouTube (including Kids YouTube).

“One of the videos starts innocently, like the start of a Peppa Pig episode for example, but quickly turn into an altered version with violence and offensive language.

“Another video clip is going by the name of ‘MoMo’ which shows a warped white mask which is promoting children to do dangerous tasks without telling their parents.

“Examples we have noticed in school include asking the children to turn the gas on or to find and take tablets.”

It goes on to say these clips could be extremely distressing for children, and asks parents and carers to be vigilant when their child is using any device or watching any clips.

Northcott School in Hull‏ also tweeted a warning telling parents the video is appearing in games like Fortnite and Peppa Pig to avoid detection by parents.

National Online Safety tweeted: “Today we’ve heard from hundreds of concerned schools and parents about the horrifying #Momo challenge which has reportedly been appearing in children’s YouTube videos, causing panic and upset amongst young people.”

It followed this with advice and guidance for parents including in setting parental controls, and reporting and blocking any offending material.

The school warnings come after a statement from the Police Service of Northern Ireland.

Detective Sergeant Elaine McCormill from PSNI’s Public Protection Branch, said: “Whilst no official reports have been made to police, we are aware of the so-called Momo challenge and are already liaising with other UK police services to try to identify the extent of the problem and to look for opportunities to deal with this issue.

“This extremely disturbing challenge conceals itself within other harmless looking games or videos played by children and when downloaded, it asks the user to communicate with ‘Momo’ via popular messaging applications such as WhatsApp.

“It is at this point that children are threatened that they will be cursed or their family will be hurt if they do not self-harm.

“I am disgusted that a so-called game is targeting our young children and I would encourage parents to know what your children are looking at and who they are talking to.”

A YouTube spokeswoman said: “Contrary to press reports, we have not received any evidence of videos showing or promoting the Momo challenge on YouTube.

“Content of this kind would be in violation of our policies and removed immediately.”

No links or videos that violate the online giant’s guidelines or promote the Momo challenge have been flagged with YouTube.