Ukips's official General Election candidates have been caught posting racist and offensive material on the internet, revealing disturbing links between Nigel Farage's prospective MPs and far-Right groups.

The Mail on Sunday can reveal that at least six Ukip candidates have circulated or endorsed material from the British National Party and other nationalist splinter groups with racist neo-Nazi agendas.

Ukip last night launched an investigation into the offensive media found by this newspaper that included a racist BNP cartoon depicting violent stereotypes of black people, Muslims and Sikhs, and online links to extremist groups Britain First, English Defence League and Infidels of Britain.

The revelations will provoke uproar on the very weekend that Ukip held its Spring Conference, with leaders disassociating the Eurosceptic party with any hint of extremism within its ranks ahead of the May 7 Election.

Pictured is the image which was retweeted by Bill Walker, the Ukip candidate in Aldershot, Hampshire

Bill Walker, 59, left, who is standing for Ukip in Aldershot, Hampshire, retweeted a British National Party cartoon (above). The cartoon, which had been posted to Twitter by Ukip activist David Jones, was drawn by fascist artist Farstar88 who uploaded it to the white nationalist website Stormfront in 2008

Bill Walker, the party's candidate in Aldershot, Hampshire, reposted a picture of a racist cartoon featuring a black man holding guns with 'Kill Whitey' on his T-shirt, a Sikh man holding a knife with 'Honour Killing Rocks' on his T-shirt and a Muslim man holding a grenade and a Koran in his hands with 'Death to the Infidels' scrawled on the front of his Islamic dress.

A man in a suit standing on a 'British Media' soap box gestures towards a white family wearing Union Jacks and St George symbols and says: 'As you can see, THIS is the problem that must be stamped out in our country.' The cartoon, intended to stir up racial tensions, was drawn by a far-Right artist based in South Africa who goes by the name Farstar88. It was originally uploaded by the artist to the white nationalist internet forum Stormfront in 2008 under the heading 'my latest cartoon for the BNP'.

Mr Walker, 58, a former soldier from Farnborough, Hampshire, retweeted the cartoon on January 11 from the Twitter account of a Southampton-based Ukip activist called David Jones who had added the comment: 'Brits are treated like second-class citizens in their own country.' The cartoon was branded 'disgusting' by anti-racism groups last night.

Simon Cressy, a spokesman for Hope Not Hate, said: 'Nigel Farage attempts to hoodwink the public and insists his party and candidates aren't racist, yet these revelations aren't going away.'

Several candidates have 'liked' the pages of the English Defence League and Britain First, an ultra-Right BNP splinter group, on Ukip Facebook profiles which are being used to campaign for votes.

'SHARED' BRITAIN FIRST POST Michael Waddington, standing in Pendle, shared a post by Britain First, which is led by the BNP’s former head of publicity. Advertisement

'LIKED': INFIDELS OF BRITAIN Steve Wood, 54, Ukip’s candidate for Bristol South, lists Britain First and also Infidels of Britain among his Facebook likes. Advertisement

'LIKED': ENGLISH DEFENCE LEAGUE Bexhill and Battle candidate Geoffrey Bastin, 69, ‘liked’ the EDL on Facebook. Advertisement

'SHARED': BRITAIN FIRST POST Steve Emmens, 49, standing in Norwich South, shared a post by Britain First – a far-Right splinter group of the British National Party. Advertisement

There are also 'likes' and posts of material from Infidels of Britain, an “ethno-nationalist” group which calls for the repatriation of 'non-indigenous' people living in the UK.

Barry Elliott, who is standing for Ukip in Blyth Valley, shared on his Facebook page an 'Infidels of Britain' picture of the late Tory MP Enoch Powell with the caption 'I tried to warn you' – in reference of Powell's infamous 'Rivers of Blood' 1968 speech against immigration – which Ukip MP Douglas Carswell insisted was 'wrong' in a newspaper article this week.

Geoffrey Bastin, the party's candidate in Bexhill and Battle in East Sussex, 'liked' an EDL page on his Facebook page, while Michael Waddington, the Ukip candidate in Pendle, and Steve Emmens, standing in Norwich South, both shared posts by Britain First last May.

Steve Wood, who is standing in Bristol South, also lists Infidels of Britain and Britain First among his Facebook likes.

THE 'INFIDELS OF BRITAIN' FAN Blyth Valley candidate Barry Elliott, 48, shared a Facebook post from far-Right group Infidels of Britain Advertisement

Ukip has repeatedly distanced itself from Britain First, which has been accused of stirring racial hatred after its activists 'invaded' mosques and handed out Bibles to Muslims. The far-Right party is led by Paul Golding, a former BNP councillor and head of publicity, and describes itself as 'a patriotic political party and street defence organisation'.

It pledged its support for Ukip during the recent Rochester and Strood by-election, posting on Facebook: 'Ukip at the ballot box, Britain First on the streets – a winning combination!' A Ukip spokesman denied the party had any links with far-Right groups last night, and said: 'These Facebook likes and other online actions will be investigated and considered at the earliest opportunity by the National Executive Committee as part of an established disciplinary procedure.'

All Ukip candidates named in this report were contacted for comment yesterday. Mr Waddington denied knowing Britain First was a far-Right group when he shared one of the party's Facebook posts about memorials for murder victims Stephen Lawrence and Lee Rigby.

'He has never been a member of the BNP, Britain First or National Front and never will be,' said John Stanyer, Ukip's North West chairman, who spoke on Mr Waddington's behalf.