A SECRETIVE Brexit backing group on Facebook have spent more than quarter of a million pounds encouraging users to lobby their MPs to “chuck Chequers,” according to evidence submitted to a Westminster committee.

The group Mainstream Network have no address, are not registered with any regulatory body and have no named reporters, managers or campaigners.

Yet their pro-Brexit, anti-Chequers messages are estimated to have targeted between 10m and 11m people on Facebook.

According to the company 89up, Mainstream Network have spent around £257,000 on their campaign in the last 10 months.

That’s almost double what UKIP has spent.

The firm have also been accused of breaching strict European data laws.

One of the digital adverts discovered by 89up encourages users to email their MP asking them to “chuck chequers.” When clicked on, the advert then generates a pre-written email lobbying their own MP on the Chequers deal.

89up say this email is in breach of GDPR rules as it sneakily, automatically keeps the users' own email address. This, the firm say, is most likely to allow Mainstream Network to continue contacting the sender.

News stories posted on the Facebook page are overwhelmingly positive about Brexit, and massively negative about the EU. They also target George Soros, the Hungarian born billionaire behind the Open Democracy campaign, who is a frequent target of the alt-right.

There are also stories attacking the SNP and Nicola Sturgeon.

In their submission 89up said: “Facebook claims to be tackling fake news but individuals or groups with a political agenda can still remain entirely anonymous on the platform and reach millions of people.”

Details of the investigation were sent to the Digital, Media, Culture and Sport select committee as part of their investigation into fake news.

Damian Collins who chairs the committee said: “Here we have an example of a clearly sophisticated organisation spending lots of money on a political campaign, and we have absolutely no idea who is behind it. The only people who know who is paying for these adverts is Facebook.

“While debate on one of the central issues facing our country is part of a thriving democracy, there is an important question of where campaigning stops and political advertising starts. Facebook has recently announced a set of changes to increase transparency around political advertising on its platform. This example offers Facebook an opportunity to show it is committed to making that change happen – if you are targeted with a message or asked to do lobby your MP, you should know exactly who is behind the organisation asking you to do it.”

Mainstream Network did not respond to The National’s request for a comment.

Meanwhile, former deputy prime minister Sir Nick Clegg has landed a senior job with Facebook.

In a surprise move, Clegg, who led his party to a brutal defeat in the 2015 election, losing them 4.4m votes and 49 MPs, will now be the social media giant’s vice-president of global affairs and communications.

The former MP said it was “a wrench” to be “leaving the public debate at a crucial time in the Brexit process,” but felt it best to quickly take up his “unique new challenge at Facebook”.