Senior Sinn Féin politicians have been criticised after attending the funeral of veteran republican Bobby Storey.
The funeral in west Belfast on Tuesday attracted hundreds of mourners, despite coronavirus regulations stating a maximum of 30 people are allowed to gather together outdoors.
Deputy First Minister Michelle O’Neill and Finance Minister Conor Murphy were among those present.
Health Minister Robin Swann said no-one was exempt from the regulations.
The PSNI said it would review footage of the funeral and “consider any suspected breaches of the Health Protection (Coronavirus Restrictions) Regulations NI 2020”.
Speaking at the Stormont briefing on Tuesday, Mr Swann said that he hoped “this isn’t the Dominic Cummings effect in Northern Ireland because quite frankly our health service can’t afford it to be.
“There is no person, or position, or point of privilege that is above the guidance we had laid down, no one is immune from it,” he said.
At Monday’s Stormont briefing, Ms O’Neill said those “attending the funeral should observe the public health advice”.
“We have had no deaths today and we have zero people in our intensive care units today because of the actions of the people in Northern Ireland, so I have a very clear ask: Please don’t let this weaken your resolve or your ability to follow the guidance that has got us to this point,” said Mr Swann.
At the same briefing, the chief medical officer said he had not yet seen photos from the funeral procession but “if there are people coming together in close proximity and there is indeed no social distancing then that does increase risk of transmission”.
In a tweet, Justice Minister Naomi Long said that when the rule makers break the rules it is more hurtful “for all who made huge sacrifices to obey the regulations”.
She said that gathering in crowds “for any reason is dangerous”.
There have been a number of events which have been criticised for attracting crowds during the Covid-19 pandemic.
In May, a senior police officer said there had been social-distancing breaches at funerals in both the unionist and nationalist communities.
Earlier in June, protestors at Black Lives Matter rallies in Belfast and Londonderry were fined, while several hundred people took part in a “save our statues” rally at Belfast City Hall.
Mr Campbell, MP for East Londonderry, said he had raised concerns with the chief constable ahead of the funeral.
He said: “The law must be upheld, that must not only happen but be seen to happen.
“We will all be able to see people there who we know and the police will know.
“No-one should expect to get a bye-ball because of their position.”
Sinn Féin leader Mary Lou McDonald, former leader Gerry Adams and Northern Ireland assembly members (MLAs) Gerry Kelly and Martina Anderson also attended the funeral.
The party has been contacted by the BBC for a response.
Speaking earlier on Tuesday at the health committee, Mr Swann said it was important the executive – made up of the DUP, Sinn Féin, the SDLP, UUP and Alliance – was seen to be “standing together giving a consistent message”.
In the assembly, Traditional Unionist Voice leader Jim Allister said the executive’s credibility had been undermined by the appearance of the deputy first minister and other MLAs “in flagrant breach, it would appear, of some of those regulations”.
At the scene: ‘Social distancing was impossible’
By Julian O’Neill, BBC News NI Home Affairs Correspondent
This was a large scale public event.
Roads and streets were closed off and Sinn Féin stewards were used to try to control things.
But such were the numbers, social distancing was impossible.
Access to the church was restricted, but those attending far exceeded guidelines.
Among those who went inside was Sinn Féin’s hierarchy, including Michelle O’Neill and Mary Lou McDonald.
They were filmed going in without masks.
When they emerged afterwards they, like some mourners, had them on.
The only PSNI officers seen in the vicinity of the church looked to be on traffic duties.
Mr Storey died at the age of 64 following a period of illness.
He was considered the head of intelligence of the IRA for a period from the mid-1990s and was named as such under parliamentary privilege.
Security sources linked him to several major incidents, including the £26m Northern Bank robbery in 2004.