First Minister Peter Robinson tonight accused Sinn Fein's Gerry Kelly of reckless behaviour after he was seen clinging to the bonnet of a moving PSNI Land Rover.
The DUP leader has waded into the debate on the incident which happened after a contentious Orange Order parade in Belfast.
Mr Robinson said: "Anybody that views the video evidence will consider it to have been reckless and ill-advised.
"No one should interfere with the police during the conduct of their duties.
"Being an elected representative and even being a member of the Policing Board does not afford him any role in the operation of police or giving police instructions on the site."
The incident is being investigated by the Police Ombudsman and was also raised in the Assembly chamber.
During a visit to a factory in Belfast, Mr Robinson said MLAs should follow proper procedure.
"He (Mr Kelly) felt he had the authority to instruct the police to stop. Anyone who has any misgivings about how police handle the issue, there is a proper process to go through that does not include blocking police in the execution of their duty, that is a bad example to set and I hope it won't have a bearing on the rest of the parading season," he added.
The incident was filmed by Republican newspaper An Phoblacht:
Meanwhile the Police Federation of Northern Ireland, which represents thousands of rank and file police officers, has called for the PSNI to investigate those who were involved in punching and kicking the Land Rover as well as senior politicians who intervened after the arrest of a teenager.
Chairman, Terry Spence said: "These matters are the subject of a Police Ombudsman investigation.
"I am in no doubt a parallel investigation will be launched. There has to be. Not only for those involved in public disorder but also the actions of some politicians."
Video footage shows north Belfast MLA and Policing Board member Mr Kelly being carried a short distance on the front of a moving police vehicle. He later described the actions of the PSNI as reckless and dangerous.
Stormont Culture Minister Caral Ni Chuilin received hospital treatment for an arm injury sustained during the same incident which followed the annual Tour of the North parade in Belfast on Friday night.
Both MLAs claimed they were trying to de-escalate a volatile situation.
Mr Spence said political leaders should show support for the police particularly during times of heightened tension.
He said: "Police officers are the meat in the sandwich. It is a thankless job trying to protect the public and trying to ensure that public order is maintained.
"Since last July 445 police officers have been injured as a result of public disorder. Since December, as a result of the flag protests, 147 police officers have been injured.
"This is not a happy situation that police officers find themselves in. It is incumbent on citizens and democratically elected politicians to show support for the police in the discharge of their duties. That is of the utmost importance."
The Police Ombudsman has confirmed it is investigating the incident and will trawl through video footage and still photographs as well as speak to members of the public.
A senior investigator said: "We are conducting an independent investigation into what happened. We would like to hear from anyone who was in the area just before half past eight who thinks they may be able to help us, particularly in relation to the events involving the Land Rover."
It is understood the officer who was driving the Land Rover has not been suspended from duties.
In a statement the PSNI said it would co-operate with the Ombudsman's office and had launched its own investigation.
A spokesman said: "The incident involving the police Land Rover on Friday evening has been referred to the Police Ombudsman and the PSNI will fully co-operate with this investigation.
"There are a number of possible offences connected with this, and other incidents connected with the parade on Friday evening into which the PSNI will conduct a parallel investigation and, where necessary, a file of evidence on these matters will be sent to the Public Prosecution Service."
The incident was also raised in the Northern Ireland Assembly.
Traditional Unionist Voice (TUV) leader Jim Allister, who lodged a formal complaint to the Assembly's standards committee, described Mr Kelly's conduct as "loutish".
He has asked the commissioner to investigate whether the Sinn Fein representative breached the code of conduct governing the behaviour of MLAs.
"It is patently obvious that Mr Kelly obstructed a police officer in the course of his duty and has therefore breached the code. Mr Kelly's leadership and example falls well short of the expectations of the code and certainly did not provide a positive example for the wider community," Mr Allister said.
DUP Londonderry MP Gregory Campbell described Mr Kelly's actions as appearing to be the "attempted physical impeding of a police officer carrying out his duty".
Meanwhile, Jonathan Craig MLA, who sits on the Policing Board, said he too would be tabling questions on the issue.
"What happened in north Belfast on Friday evening appeared to be an attempt by a politician to interfere with the PSNI carrying out the lawful exercise of their duty.
"An Assembly member, and a member of the Policing Board, seemed to move beyond his remit of acting as a guarantor of the accountability of the police and attempted to direct a policing operation. That is not acceptable and it is only right that this behaviour is raised through the proper channels within the board," said Mr Craig.
Paul Givan, chairman of the Stormont justice committee, has called for the PSNI senior management to comment on the situation.
He took to Twitter to say: "PSNI silence on landrover incident is not good enough."
Up to 1,000 people took part in the Orange Order's Tour of the North through north Belfast. Minor scuffles broke out at the nationalist Peter's Hill area where two people including a 16-year-old boy were arrested.
"The policing operation on Friday evening was a large-scale operation for an event which passed off largely peacefully," added a PSNI spokesman.
A spokesman for Sinn Fein said Mr Kelly would not be available to comment further on the issue.