A police investigation has been launched into allegations of child grooming after two primary school pupils were approached by men on social media.

Two children from Eastgate Academy in King's Lynn were allegedly contacted by men on Musical.ly - a social media app used for creating and sharing short videos.

Parents were sent a letter from the school on Tuesday, May 23, describing the incidents and advised them talk to their children if they use the app.

The letter, entitled safeguarding, stated the children were propositioned by a man who said he is 22-years-old, and another man had asked them to go on a live chat where he exposed himself.

It said the social networking app is used by children at the school to contact each other and to add new friends. The men befriended the two pupils through the app before the incidents took place this week.

Signed by principal Linda Hothersall, the letter said: 'We have asked all children to talk to their parents if they use this app and have asked them to delete it.

'We are asking for your support with this to help us to keep our children safe.'

Mrs Hothersall added: 'Safeguarding is a priority within the academy and online safety is an integral part of our curriculum.

'We felt that it was important that all parents were made aware of the potential risks in using this app.'

A police spokesman confirmed an investigation is being dealt with by the Safe Guarding Online Team following the grooming claims.

He said: 'Following a call from the child's parents, a crime has been raised in respect of inciting a child under-13 to engage in sexual activity. The child's phone has been seized as part of the investigation.

'In terms of advice, there is nothing locally I would add to the national guidance around safeguarding children online which is essentially encouraging parents to be actively involved in their child's internet usage and to be aware of the warning signs in child's behaviour.'

The Musical.ly app is thought to be popular among young viewers, where users can create, message and broadcast live videos of up to one minute.

For more information about safeguarding children online, visit the Get Safe Online website.