Online abuse

In its cyber crime report, Europol said the use of encrypted tools, which enable offenders to stay anonymous, were now "becoming the norm".

With millions of children online, access to them was "higher than ever".

Cybercrime reporting in Europe had surpassed traditional crimes, it said.

Europol called the ability for child sex offenders to communicate, store and share materials and hunt for new victims online "one of the internet's most damaging and abhorrent aspects".

Around 52% of voters in the UK voted to leave the EU, but many have been criticised online by Remain voters.

Young Leave voters have told Newsbeat that they've been labelled racist and xenophobic for their political views.

It has resulted in many Leave voters staying silent on social media for fear of attack and criticism.

"The main place I received abuse was on Twitter," 19-year-old Thomas Proudfoot tells Newsbeat.

"People were getting quite aggressive towards me when I tweeted about how happy I was that leave won.