A self-styled “anti-extremism” and pro-“civility” group is spending thousands of pounds running anti-Labour attack adverts on Facebook focusing on the party’s tax and nationalisation policies.

Mainstream UK describes itself as “a new campaign designed to encourage a return to respectable and responsible politics, and to banish extremism from British politics once and for all”.

But despite the non-partisan branding and mission statement under which it solicits cash donations, the group’s entire advertising output is in actual fact targeted at the opposition Labour Party – the bulk of it on issues like taxation and public ownership.

Mainstream UK appears to have little organic support and is only “liked” 94 times on Facebook, but its posts have been seen by hundreds of thousands of people because it has spent thousands of pounds promoting them as adverts.

The group makes no mention of being an anti-Labour campaign on its website or Facebook page. Information on its website shows it is backed by figures including former Conservative party chair Eric Pickles, outgoing Liberal Democrat MP Norman Lamb, and broadcaster Rachel Riley.

Ex-Labour independent MPs like Ian Austin, Mike Gapes, Ann Coffey and Ivan Lewis – all vocal critics of Jeremy Corbyn’s leadership – are also listed as supporters.

An analysis of the group’s adverts show it has run three different adverts on Facebook, all anti-Labour.

One, which appears completely unrelated to the group’s stated anti-extremism purpose, reads: “REVEALED: Jeremy Corbyn said that nobody below £80,000 will pay more in tax under his government. Wrong. Watch this”. It features only a video of BBC interviewer Andrew Neil asking Mr Corbyn about dividend taxes.

Another advert features a clip from a video of actress Maureen Lipman, another one of the group’s supporters. The 10-second video simply says: “This lot’s not Labour, they’re extremists. If he could nationalise daffodils he would”. A third advert, which is currently marked inactive and not being shown to users, features a longer two-minute clip from the same video and makes reference to antisemitism in the Labour party, as well as “the throwing around of millions of pounds” by the party in spending pledges.

The three adverts are mostly about tax and public ownership (Facebook)

The group has spent £4,900 so far to show the adverts 376,000 times.

Statements on Mainstream UK’s website, which solicits donations, give little away about its actual activities. Sir Norman Lamb’s reads: “During a moment in time where divisiveness, partisanship and in-fighting have become the political norm, it is most refreshing to see a new organisation whose aim is to come together on consensus-based ideas that connect people across the political spectrum.”

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Ivan Lewis’s meanwhile reads: “When the history books are written about politics in 2019, there will be a shining light standing out amongst the darkness – Mainstream. I am proud to join a cause bringing civility and decency back into the political discourse.”