By Katrine Bussey, Press Association Scotland
Labour suffered its first casualty of the General Election campaign today as a candidate was sacked over offensive posts he made on Twitter.
Prime Minister Gordon Brown described the comments by Stuart MacLennan, who was fighting the Moray seat in the north of Scotland, as "unacceptable".
Mr MacLennan reportedly branded the elderly "coffin dodgers" and posted a series of foul-mouthed rants about politicians, including Tory leader David Cameron and Liberal Democrat leader Nick Clegg.
On the campaign trail, Mr Brown said: "A candidate has made a mistake. It's unacceptable. That candidate has got to resign.
"I have made it absolutely clear what my views are: we cannot have people standing as candidates for the Labour Party who express these views, so that candidate will not be a candidate for the Labour Party."
Mr McLennan, 24, issued a brief statement apologising for his comments.
He said: "I am very sorry. I have been stupid and rightly paid a high price."
His Twitter page has now been closed down but the Scottish Sun said he branded House of Commons Speaker John Bercow a "t**", Tory leader Mr Cameron a "t***" and Lib Dem leader Mr Clegg "a b******".
He posted an outburst about veteran Labour MP Diane Abbott, describing her as "a f****** idiot", the paper said.
Mr MacLennan also posted insults about celebrities, according to the Sun.
He reportedly called X Factor judge Louis Walsh a "c***", referred to Jedward as "odious little s***s" and wrote: "I f****** hate Paolo Nutini".
The comments drew criticism from his political opponents, who branded the remarks "vile" and "disgraceful".
Labour initially appeared to have rejected calls by opponents for him to be sacked as a candidate.
At the launch of the party's campaign in Scotland, Scottish leader Iain Gray said the comments were "absolutely unacceptable".
But he added he still had the support of the Labour Party.
Mr Gray, who was accompanied by Scottish Secretary Jim Murphy, said: "He's a very young guy, a first-time candidate. I guess we all make mistakes when we're young and he knows he's made a big mistake.
"He still has the backing of the party, he is still the candidate, he still has the backing of the local party in Moray. But I think he knows he's let them all down and he's made that very clear, and he has apologised."
Less than an hour later, it emerged from London that Mr MacLennan had been sacked.
A spokesman said Mr MacLennan had been axed as the candidate for Moray for "the totally unacceptable language which he has expressed online".
He added: "On reading the comments in full, the Scottish Labour Party was outraged by their content and Scottish Labour's general secretary took the decision to suspend his membership of the Labour Party.
"Stuart MacLennan is no longer a Labour Party candidate nor eligible to hold office as a Labour Party representative."
Mr Murphy told the BBC News Channel: "Once we became aware of all the comment he has posted on Twitter, we were left with no option but to sack this individual.
"He was a young candidate, but that's no excuse. He was keen to engage voters through Twitter but that's no excuse for the rubbish and offensive and hurtful comments that he made.
"Once were we fully aware of that, we took the right action, which was to sack him as a candidate and to suspend him from membership of the Labour Party and not to allow him to hold office in the Labour Party."
Asked why he had not acted sooner, Mr Murphy said: "I am not a follower of this individual's Twitter feed so I had no idea of these comments, and no-one in the Labour Party did."
He added: "I would like to apologise to Labour voters in that constituency for the breach of trust that this one individual has carried out and the way in which he behaved."
Moray's SNP MP Angus Robertson said: "Only an hour before this announcement, Jim Murphy was saying he could stay as a candidate and trying to brush off these outrageous comments.
"However, he has been overruled and clearly has no authority. Did Gordon Brown tell his Scottish Secretary what to do?
"This incident has completely devastated Labour's campaign launch today - but questions must be asked as many of these comments have been online for months, and presumably Labour colleagues have been well aware of them."
The Conservatives and the SNP said senior Labour figures, including Ed Balls, Andy Burnham, Ben Bradshaw and John Prescott, had been followers of Mr MacLennan's Tweets.
Scottish Tory leader Annabel Goldie said: "To describe, as Mr Murphy and Labour tried to do, foul-mouthed rants against elderly people, women, ethnic minorities and others as 'foolish' is appalling.
"It was repugnant, insulting and totally in character with Labour's desperate and dirty campaign.
"What staggers me is senior Labour figures, including Ed Balls, Andy Burnham, Ben Bradshaw and John Prescott, condoned this behaviour for so long by following his Tweets without protest.
"Labour clearly didn't care about this type of smearing and dirty politics until it was exposed."
SNP leader and Scotland First Minister Alex Salmond said Labour had descended into "a total shambles".
He said: "Obviously it is the right thing that somebody who insulted all of Scotland's old age pensioners can't stand as a candidate.
"The problem the Labour Party now has is it is now emerging many leading Labour figures, senior politicians, Cabinet members, Shadow Cabinet members of Scotland, were followers on his Twitter.
"So they knew the sort of things he was saying. They knew this candidate was insulting the pensioners, insulting the north of Scotland, demeaning Scotland's greatest national product, but did nothing about it.
"The Labour Party have moved on from being an issue affecting one candidate to now a question of who knew what, when.
"They stand accused not just of total incompetence and disarray, but of complete and utter hypocrisy."
He went on: "The interesting thing is, it is now emerging the followers on his Twitter were Ed Balls, Wendy Alexander.
"Leading Labour Party figures knew about what he was saying and presumably thought it was all right so long as nobody knew about it."
Liberal Democrat Scottish spokesman Alistair Carmichael said: "The Labour Party has been forced to sack a candidate who was clearly young and inexperienced.
"This whole debacle only demonstrates the weakness of Labour in Scotland."
It later emerged Mr MacLennan was summoned to Labour's Scottish headquarters in Glasgow today, where he was sacked.
Party bosses originally believed the comments were made some time ago, but when it became apparent that some were made more recently, they acted.
The decision leaves members of the local party in Moray searching for a new candidate.
A Scottish Labour Party spokesman said activists in the area would meet "in the next day or so" to do this.
He added: "We expect a new candidate to be in place in the next couple of days."