The PSNI has defended how it dealt with a flute band taking part in Saturday's Apprentice Boys parade in Londonderry.
It follows an investigation by officers into the display of a parachute regiment symbol bearing the letter F on one band's uniform.
Soldier F is a veteran of the regiment who is facing prosecution over Bloody Sunday.
Nationalists say the band's actions have caused hurt to victims. Unionist politicians have accused the PSNI of 'heavy-handedness' after the band's bus was stopped on the outskirts of the city on their way home.
Speaking on Monday, Assistant Chief Constable Alan Todd denied this and insisted the response was proportionate.
“I see no grounds for using that description," he said.
“Our engagement before, during and after the parade, were by way of discussion and negotiation. It was proportionate, responsible and and constructive.”
ACC Todd said police took steps to identify the band members in question in order to put the facts before the Public Prosecution Service, and once those details were obtained the group was allowed to move on.
“The event passed off peacefully, people were kept safe, no one was hurt and no one was unduly inconvenienced by those police actions.”
In a statement on Monday evening, Clyde Valley Flute Band denied their uniform was deliberately provocative, stating it has been worn by members on previous occasions "without incident or controversy".
They added that they believe their detention was unlawful, and that they believe no offence has been committed by the band.
They said not withstanding those matters, they would co-operate fully with police but added they are considering making a complaint to the Police Ombudsman.
DUP East Londonderry MP Gregory Campbell, who was there for the parades on Saturday said the party's Policing Board members would be demanding answers.
He said this was in relation to their engagement with the band members but also an alleged request to take down a banner in support of British soldiers, which Mr Campbell said made no reference to Soldier F.
He said: “It is absolutely essential that the rationale for Policing operations is seen to be justifiable and even handed irrespective of the location, or of those being subjected to the police actions.”
Sinn Féin Councillor Christopher Jackson said the band’s actions were “a deliberate attempt to stir up tension and hurt the families of the Bloody Sunday victims.
“Sinn Féin will be raising this incident with the Parades Commission and the police to ensure it does not happen again,” he commented.
WATCH: Mark McFadden looks at how intensive talks in the 1990s calmed tensions surrounding parades in Londonderry