Children as young as 13 are joining Nazi groups which are increasingly turning towards Satanism, a new report warns.

Research has found a “disturbing” trend among the far right which is “getting more extreme and younger”, with those with dangerous ideologies finding each other online.

Matthew Collins, a researcher at counter extremism group Hope Not Hate, which produced the report, said that the emerging groups are made up of “clever, mostly perverse young men” who are meeting in hidden areas of the internet and encouraging each other to become more extreme.

He said: “As a result we are seeing more and more about Satanism and white jihad. It is almost like Hitler isn’t extreme enough for them anymore.

“They are not like the traditional far right groups - they are more articulate, they are certainly more sophisticated and they are finding each other on gaming websites and things like that.”

The numbers joining these groups are in the hundreds, but it is feared that those who are radicalised online will go on to commit offences offline.

The Security Services warned of a growing threat from the far-right in the wake of the Finsbury Park mosque attack and the murder of MP Jo Cox.