The NUJ has expressed concern at an increase in intimidation and bullying of journalists covering the independence referendum and is calling for people on both sides of the campaign to rein in the abuse.

Paul Holleran, NUJ Scottish organiser, said: "People have the right to protest if they believe strongly about an issue, however protesters outside the BBC offices in Glasgow this weekend have demanded that journalists be sacked for allegedly being biased in favour of the union.

"We have also experienced a number of Labour MPs, accusing the corporation's most experienced and talented journalists of political bias against the Better Together campaign. This highlights the fact that people on both sides are accusing the BBC of bias.

"Journalists in Edinburgh and Aberdeen were abused over the weekend when simply turning up to report on events organised by both sides.

"Others were on the receiving end of a range of abuse and intolerance on social media, some of which has been logged and may be reported to the police."

He added: "Robust debate is fine. Pointing out when journalists get their facts wrong is expected and welcomed. But NUJ members believe in a free press, a fair media, with journalists allowed to do their jobs free of intimidation.

"We hope the politicians and campaigners, and those who follow politics take this on board and act with a bit of maturity and understanding of the role of journalists in holding those in power to account.

"What is totally unacceptable is the use of threats of violence. The NUJ has a history of acting on this type of behaviour and Police Scotland has been supportive and has intervened when we have previously pursued such action."

The union said it would name and shame individuals and organisations that continue to threaten or bully its members.

It added in a statement: "There are massive political decisions ahead for Scotland and the independence referendum campaign is coming to a frenzied close. The NUJ believes there will and should be increased opportunities across the media for robust exchanges, challenging all participants in the debate but carried out in a civilised manner.

"The union believes it is essential that respect is shown to participants if journalists are to maximise the number of people willing to take part in those debates. They also need to respect the role of journalists in fairly moderating those debates, and refrain from intimidation and personal abuse.

"In particular, the NUJ is concerned about threats about future employment at the country's main broadcaster as well as public labelling of journalists and programmes as being biased. As the public service broadcaster, BBC Scotland's journalism is rightly scrutinised very closely by people and parties on all sides of the political debate.

"No journalist working for the organisation has a problem with this but they have been singled out by demonstrations which by and large have been loud and rowdy but can be perceived as being intimidatory and a threat to press freedom.

"There is an increasing trend towards the intimidation of BBC journalists, who are working hard to hold politicians of all sides to account in the referendum debate."