A solicitor representing the family involved in the Manchester Airport incident said they had spoken to the IOPC with “regards to lodging a formal complaint against officers”.

Protests erupted in Rochdale and Manchester city centre after a video circulated of a police officer allegedly kicking and stamping on a man as he lay face-down during an arrest at the airport on July 23.

A Greater Manchester Police constable was advised he is under criminal investigation for assault over the incident, the Independent Office for Police Conduct (IOPC) said last week.

Greater Manchester Mayor Andy Burnham urged people to “take a step back” and allow the authorities to carry out their investigations after the Manchester Evening News published new footage thought to show the lead-up to the incident.

Fahir Amaaz, 19, Muhammad Amaad, 25, and their mother Shameem Akhtar, 56, said they wanted to understand “on what legal basis” Mr Burnham was shown complete CCTV of the incident “and by whom”.

Through their solicitor, Aamer Anwar, they said the family and its legal representatives should have been “provided with an opportunity to view footage before any politician”.

They added that leaked footage “does not show exactly what the police did” and criticised “attempts by so-called ‘police sources’ to spin a false narrative or partial context”.

The video published by the Manchester Evening News appeared to show a group of people standing by ticket machines in terminal two (T2) and a man in a light blue outfit facing one of the machines.

Male and female officers appeared to attempt to restrain two men who were involved in a series of strikes and punches before one man was tasered.

An officer and a man in blue appear to grapple until the latter lies still on the ground, face-down, and a woman kneels by his side.

The officer then appears to kick and then stamp on his head, which was shown in the footage already widely circulated.

Mr Anwar said if family members had engaged in criminality, “then they must be subjected to due process”.

He added that there could “never be any legal justification” for the “use of excessive, disproportionate and potentially lethal force against a civilian who is incapacitated and poses no threat”.

In a statement issued on Thursday, Mr Anwar said: “I have now spoken to the IOPC with regards to lodging a formal complaint against officers from Greater Manchester Police.”

The family’s solicitor added: “We also seek to understand on what legal basis Andy Burnham was shown the complete CCTV and by whom.

“The repeated attempts by so-called ‘police sources’ to spin a false narrative or partial context is deeply unhelpful to an IOPC investigation.

“Leaked footage does not show exactly what the police did, how the incident unfolded, nor the full conduct of officers in the aftermath of the incident in all parts of the airport, including after the arrests.

“As for leaking of CCTV, we understand that will also form part of their investigation, but whilst it may be blatantly obvious who would benefit from such a cynical and partial leak, proving who the individual or ‘institution’ is likely to be impossible.”

Mr Anwar added that the family expected all material relating to the incident and cameras of the aftermath to be retained, “especially those where the detainees were taken to in other areas of the airport”.

The family and their solicitor will attend a press conference in Manchester on August 6.