A Northern Ireland reporter who witnessed the murder of journalist Lyra McKee in Derry last April has received renewed threats in the city.

Graffiti branding Leona O’Neill a “tout”, or informer, and falsely linking her to MI5 appeared in Derry’s Creggan area on Tuesday evening.

O’Neill, a Belfast Telegraph columnist and freelance writer and broadcaster, posted a picture of the graffiti on Twitter last night, which also denounced her as a “shit stirrer”.

The National Union of Journalists (NUJ) condemned the graffiti as “vile and dangerous”.

It is understood the latest threats to O’Neill came about after she revealed that a republican flute band with links to Saoradh – the political allies of the New IRA – had taken part in a Bloody Sunday commemoration march in the city last weekend.

The presence of Saoradh and its supporters at the march created controversy in Derry. The Bloody Sunday Trust said Sunday’s march had nothing to do with it.

Tony Doherty, the trust’s chairman, whose father, Paddy, was one of 13 civilians shot dead in the city by the Parachute Regiment in 1972, said anger over the presence of Saoradh and an aligned band was misplaced.

“We don’t normally court controversy but we want to make it clear that we don’t have any association with that march,” he said.

Responding to the graffiti, O’Neill said: “I am neither a MI5 tout nor a shit stirrer. I am a journalist, working in my city trying to provide for my family. I consider this a threat to my safety. I call on community leaders to help me get this dangerous slur removed now.”

In a joint statement, the NUJ’s general secretary, Michelle Stanistreet, and assistant general secretary, Séamus Dooley, said there could be no place in a democracy for such behaviour.

“We strongly condemn this vile and dangerous threat. It is a clear attempt to intimidate a hard-working, committed journalist. Leona has proven herself to be a journalist of resilience with a strong passion for Derry. We would call on civic and community leaders to support journalists and to defend media freedom.

“Journalists must be free to report without intimidation. To describe a journalist as an agent of a police force is dangerous and poses a threat to their ability to do their job,” they added.

Last year Twitter and Facebook came under pressure to take action over an online hate campaign against O’Neill.

The Derry-based journalist has been subjected to consistent abuse from conspiracy theorists and internet trolls after witnessing Lyra McKee being killed by a New IRA gunman during riots in Derry in April 2019. The abuse has included false accusations that she had made up her account and even that she was responsible for the killing.

McKee’s murder grabbed worldwide attention as she was the first reporter to be killed on duty in Northern Ireland since the Sunday World investigative journalist Martin O’Hagan was shot dead by loyalists in 2001.