Drill music videos laden with references to violence are being forced onto porn sites in a bid to avoid being taken off the internet.

Detectives say the clips, often associated with bloody gang rivalries, have started appearing on sites like Pornhub.

Police began a concerted crackdown on certain drill videos on the mainstream internet around three-and-a-half years ago, and since then around 400 have been taken down.

Harmful content can be removed from YouTube, which allows police officers to flag items of concern on its internal system, in less than an hour.

Metropolitan Police temporary Detective Chief Superintendent Mike West said: "We are seeing videos pop up on other channels, pornography platforms. They're being forced off the mainstream channels into other places.

"We've seen drill tracks appearing on Pornhub."

The work against the most violent elements of drill has led to the creation of a new unit of eight young Met officers who are using cutting-edge ways of gleaning intelligence from social media to stop serious gang-related violence.

All Pcs aged under 25, they have previous experience of working in gang units, many grew up in crime-ridden parts of the capital and have knowledge of the slang and code words used for drugs and weapons.

Set up in June, Operation Alpha has already dealt with 800 taskings and is operating as a pilot for five other UK police forces.

Mr West said: "They spot threats in a different way. The terminology used by gangs, the differences between south London and north London, and the type of slang used.

"We want to be on the front foot of open source intelligence. This is about understanding what is a threat now, what is a threat today.

"We are stopping serious offending happening, serious violence, firearms-related crime, knife-related crime, knife sales, drug dealing on Snapchat and Instagram at scale.

"Offences in prisons is a massive piece of our work. Anything from assaults to the importation of drugs into prison in fairly sophisticated ways, stuff I've never seen before in my 24 years in the Met."

Earlier this year, the team was able to stop hooded gangs who were storming branches of JD Sports.

They worked out where the thieves were planning to strike next, allowing the chain to beef up security and stop the raids within 24 hours.

A number of other prosecutions are due to come to fruition in the new year.

Pornhub, Snapchat and Instagram have been approached for comment.