More than 300,000 pieces of terrorist material have been removed from the internet in the last eight years.

'ACT - Action Counters Terrorism campaign' which deals with online terrorist material, is now reminding people to report suspicious activity.

The unit has also provided key evidence and information in 226 counter terrorism investigations since it was established in 2010.

Commander Clarke Jarrett, head of the Counter Terrorism Command at the Metropolitan Police, said: "It's vital that if the public see something online they think could be terrorist-related that they ACT and flag it up to us.

"Our Counter Terrorist Internet Referral Unit (CTIRU) has specialist officers who not only take action to get content removed, but also, increasingly, are in a position to look at those behind online content - which is leading to more and more investigations."

Online terrorist-related material can be reported via http://gov.uk/act

In 2010, the UK established the world's first ever Counter Terrorism Internet Referral Unit (CTIRU), hosted within the Met's Counter Terrorism Command, to tackle the rise in terrorist-related material that was appearing on the Internet.

Since the CTIRU's launch, just over 304,000 pieces of terrorist-related material have been removed from the Internet.

The majority of this content relates to Islamist extremism, but the unit has also seen an increase over the past year in content related to extreme right-wing ideology.

Around a quarter (481 = 26%) of all public referrals (1849) into the unit since March 2017 related to extreme right-wing material, although the vast majority of public referrals still relate to Islamist extremism.

In previous years the CTIRU has been focused on getting terrorist content removed from the Internet.

But as their work and relationship with internet providers has developed to a point where more and more of the material is being removed automatically by the content providers themselves, the unit has been able to shift focus towards investigations.

As a result, over 226 counter-terrorism investigations across the UK have been supported or been provided with key evidence and information from the CTIRU.

Mohammed Kamal Hussain, from Whitechapel, was jailed in February for encouraging terrorism and supporting a proscribed organisation.

A suspicious message had been sent to somebody living outside the UK, who then contacted UK authorities in March 2017 to alert them to the message.

The CTIRU made further enquiries and established the message was from a man - Mohammed Kamal Hussain, 28, from Whitechapel.

A fast-time investigation was launched by the Met Police Counter Terrorism Command who arrested Hussain on June 30, and he was subsequently convicted and jailed in February.

Commander Jarrett said: "I would urge anyone who comes across what they think could be extremist or terrorist material - whether it's right wing, Islamist or indeed any other form of extremism - to report it to us.

"Our specialist officers can then assess the material and take appropriate action to potentially prevent further terrorist activity from happening."