A meeting between Sinn Féin and Northern Ireland's chief constable following a controversial operation at a commemoration of a loyalist atrocity has been described as "forthright" and "frank".

The party's vice president Michelle O'Neill said she told Simon Byrne of "unprecedented anger" over the arrest of Mark Sykes, a victim of the Sean Graham bookmakers shootings. 

It came days after police officers were seen standing by as dozens of masked loyalists walked around an area of east Belfast. 

Ms O'Neill said the series of events has created a "crisis in public confidence in policing". 

"I left the chief constable in no doubt that the events of recent days are a watershed moment for policing and public confidence in policing," she said. 

The chief constable is meeting with representatives of all the main parties. 

Speaking ahead of his party's meeting with Mr Byrne, UUP MLA Mike Nesbitt said the incident on the lower Ormeau Road last Friday was "very unfortunate" but "no excuse for any politician to use it to question or undermine confidence in the police service". 

Five people were murdered in the UFF atrocity at the Sean Graham bookies in 1992

Yesterday, Mr Byrne denied being in "anyone's pocket" as he expressed concern police were being used as a shock absorber in intensifying political clashes. 

He also rejected claims commanders had scapegoated two inexperienced officers sanctioned after the arrest of Mr Sykes. 

In an interview with the PA news agency, Mr Byrne dismissed allegations levelled from both sides of Northern Ireland's traditional political divide that the police adopt different approaches for different communities. 

"We have been bashed frankly by recent events and it just seems sometimes that we can't seem to win," he said. 

The police chief again made clear he had no intention of resigning. 

"It's been a tough week, but I'm not the first chief constable here that's had to suffer or be accountable... for criticism over the last 50 years," he said. 

"Actually quitting is the easy thing and whatever next week looks like, frankly, the in-tray is the same and I'm just determined to carry on with the support of my team to actually deliver what we set out to do." 

There were angry scenes on Friday when police challenged commemoration participants amid suspicions the size of the public gathering breached coronavirus regulations. 

Mr Sykes, who was shot several times in the 1992 outrage, was handcuffed and arrested in chaotic exchanges captured on social media. 

He was released a short time later. 

The conduct of the two sanctioned officers is being examined by the independent watchdog, the NI Police Ombudsman. 

The episode followed just days after police officers failed to arrest anyone when they encountered a large gathering of masked loyalists staging an apparent show of strength in east Belfast. 

The incidents came in a week when police were also dealing with increasing tensions over Brexit that led to the withdrawal of staff conducting trade checks at Larne and Belfast ports amid safety concerns. 

"I think this has been a unique week, I've never known anything like it in my professional police experience," Mr Byrne told PA. 

The PSNI has also been facing claims of discriminatory policing from loyalists and unionists, who are angry that officers have not intervened when large crowds have gathered for the funerals of former IRA men. 

The most high-profile of these occurred last June when senior Sinn Féin figures joined hundreds of mourners at the funeral of well-known republican Bobby Storey. 

"Sometimes you just feel like we can't do right for doing wrong," said Mr Byrne. 

He added: "I recognise here that there is often different and competing political views and actually sometimes the police are the shock absorbers of all of that sort of narrative. 

"I think it's about resolve and resilience and keeping on our path to be impartial and we're here to uphold the law. 

"I can't stop political commentary, nor would I want to, I think it just would be important at the moment for political space, so that my officers and team and staff can carry on with the issues of policing rather than getting involved in the political debate." 

In regard to claims from some unionists that the move to suspend one officer and reposition another was pandering to Sinn Féin, he said: "This was an objective evidence-based decision, we looked very carefully at what we did. 

"By no means was it a knee jerk, we're not in anyone's pocket but it was recognising this was a serious matter." 

He denied scapegoating the two officers, who only joined the PSNI last July. 

"We weren't influenced by anybody else, we weren't pandering to criticism or any other inferences," he said. 

"I fully understand some of the accusations but we have to work within due process and actually look at the conduct regime that informs our decisions, sometimes they are not popular but this isn't about scapegoating, there's a process that will now take place, we don't presume what the outcome is." 

In terms of enforcing Covid-19 regulations, Mr Byrne highlighted the challenge of keeping pace with legislation that had been changed multiple times in less than a year. 

He said: "Sometimes people say we got the balance wrong, but at the end of the day I think a number of things collide here - firstly, it's fast law, regulations have changed, tactics have had to change to keep pace with that, but public expectations haven't. 

"And I think frankly in terms of people's feelings and emotions, people are tired or frustrated and want to see a route to normality and sometimes we're caught up in all of that." 

Mr Byrne added: "What I'm appealing for people is effectively to dial down the tone, for calm, wise heads to help us in a route to normality, whether it's in the context of EU exit, policing the regulations or the day-to-day policing. 

"We have a job to do and we need the space to get on with it."