Unionists have condemned the erection of a banner celebrating an IRA hunger striker at a County Down play park.
The banner describes Raymond McCreesh, who was caught in possession of a gun used in the 1976 Kingsmills massacre, as a "hero".
It has been described by Ulster Unionist councillor David Taylor as "sick".
In a tweet, former DUP first minister Arlene Foster said it was "wrong on so many levels".
She added: "Raymond McCreesh was arrested whilst in possession of the rifle used by the PIRA to murder 10 Protestant workmen in 1976.
"Glorifying those who used terrorism only serves to confuse the next generation."
The naming of the Newry park after the IRA man has been controversial since it opened in 2001.
Last year, the SDLP voted against renaming it in an effort to "avoid stoking community tensions".
Cllr David Taylor appealed to Sinn Féin leader Michelle O'Neill and local party members to condemn the banner and ensure its removal.
"To call a man who was caught in possession of one of the guns used at Kingsmills 'our hero' is beneath contempt," he said.
"It is a deliberate insult directed at McCreesh's victims and an insult to the memory of those murdered and injured in the Kingsmills massacre.
"I am deeply disappointed and shocked at the endorsement of this banner by Ballybot residents. By doing so they are causing deep offence to a great many people, including their Unionist neighbours."
A Sinn Féin spokesperson said: "This issue has arisen because Arlene Foster has again publicly criticised the Raymond McCreesh Park.
"It's incredible that Arlene Foster can comment on a legacy issue while remaining silent on the fact that the High Court last week ruled that she had acted unlawfully by blocking money for legacy inquests.
"When is the former First Minister going to comment on the scathing judgement handed down against her?
"And when is the media going to demand that she publicly responds to a judgement, that in any other jurisdiction, would be seen as a gross dereliction of duty by the former First Minister."