Image copyright Reuters Image caption Police have removed videos posted by so-called Islamic State

More far-right extremist and terrorist content is being removed from the internet after a growing number of tip-offs, the Metropolitan Police says.

The Met says it has removed almost 250,000 items since it began focusing on the problem in 2010.

The right-wing items include videos of meetings and demonstrations, and there were videos posted by so-called Islamic State designed to attract recruits.

Det Ch Supt Clarke Jarrett said the removal of the material was "crucial".

"We are seeing more and more material being put out by terrorist and extreme right-wing groups on the internet," he told the BBC.

"They are looking to spread extremism and radicalise others.

"We think it is really important to remove that material where we can from the internet and to stop vulnerable people finding it easily on social media sites."

Referrals from the public via an anonymous site have doubled since 2012, and 2,000 items are removed every week on average.

Public tip-offs

Specialist Met officers dealing with internet extremism say racist videos and social media posts - including content by the group National Action, which was banned by the government this month - are adding to their core task of dealing with radical Islamist propaganda.

The Met's Counter Terrorism Internet Referral Unit team makes requests to 300 internet companies around the world to take down material which is illegal under UK law.

Image copyright PA Image caption The Metropolitan Police says it has removed almost 250,000 extremist items from the internet

Officers say their relationships with social media services are generally good, but declined to name companies which prove more difficult to persuade.

They would like more of an international effort to tackle the problem, senior officers say.

The Met team was the first of its kind, but the European policing authority Europol has also set up its own unit.

Counter-terrorism officers said videos posted by so-called Islamic State also included "hearts and minds" propaganda aimed at the families of those it hopes to attract.

The biggest risk is that vulnerable or mentally-ill internet users will find extremist material online, encouraging them to carry out attacks, police said.

Journalists were shown one video in which a jihadist speaking English urged viewers who were unable to get hold of an assault rifle to buy a knife instead.