SCOTTISH Labour is “in chaos” over the constitution, the Tories have claimed, after two of the party’s candidates were caught up in rows over independence.

One was revealed as a Yes supporter in 2014, while another was found to be urging SNP voters to vote for Jeremy Corbyn in order to secure a second referendum.

Scottish Labour’s official position is absolute opposition to a second referendum.

In a day of unexpected twists for Labour, and growing questions over its vetting process, the party named Sally Prentice as its Holyrood byelection candidate in Ettrick, Roxburgh and Berwickshire, where Tory MSP John Lamont has quit to stand for Westminster.

In a press release, Ms Prentice was quoted saying she would “stand-up to the SNP in Holyrood and fight against a divisive second independence referendum”.

However it quickly emerged she had recently done just the opposite.

She wrote on her Facebook page last week: "SNP voters: the only way you're going to get to ask the question again is if Jeremy Corbyn is in number 10. I implore you to hold your nose and vote Labour on June 8th.”

She also posted a graphic declaring: "A vote for Labour in Scotland is a chance of indyref2."

MSP Rachael Hamilton, the Tory candidate for the seat, said: “This is astonishing. On the one hand, this Labour candidate is promising people she will oppose a second referendum.

"Yet on social media she is openly trying to win SNP votes by backing a second referendum.

“Either Kezia Dugdale knew about this, or has lost control over her embattled party.

"This is more confirmation that, under Jeremy Corbyn and Kezia Dugdale, Scottish Labour cannot be trusted to defend the decision we made in 2014 to stay part of the UK.”

A Scottish Labour spokesman said Mr Corbyn was clear that another referendum was “unwanted and unnecessary” and would produce “turbocharged austerity”.

He added: “Sally Prentice also firmly opposes a second independence referendum.”

It followed a row earlier in the day over Camden councillor Douglas Beattie, who is standing against Scottish Secretary David Mundell in Dumfriesshire, Clydesdale & Tweeddale.

The Tories unearthed a series of Tweets from 2014 showing he was pro-independence, although Labour said he had later changed his position to support a federal UK.

Scottish leader Kezia Dugdale said she was “really proud” Mr Beattie was standing.

“He represents lots of people in Scotland who voted Yes in 2014 and won’t do it again. He’s very clear he opposes a second referendum - he doesn’t think that’s good for our country.”