Solicitor Akhmed Yakoob told reporters that a family who say police assaulted them at Manchester Airport approached him for help.
Footage filmed at the airport’s terminal two on Tuesday appeared to show an officer kick and stamp on the head of a man who was lying face down on the floor, with a woman kneeling beside him.
The video also appeared to show the officer strike a second man.
On Thursday, Mr Yakoob spoke on behalf of the family to media gathered at Rochdale police station – the scene of a protest the night before.
He said Mohammed Fahir, 19, was “fighting for his life” from head injuries he received and that Mr Fahir’s brother and 56-year old mother were also assaulted at the airport.
The two men had arrived to pick up their mother who had flown in from Pakistan, he said.
Their elder brother, a serving officer with Greater Manchester Police, he added, was “too afraid” to go into work.
Speaking on BBC News outside Rochdale police station, Akhmed Yakoob said the incident was an example of “police brutality”, adding: “The people who were assaulted by the police are members of a police officer’s family who is currently serving in the Greater Manchester Police force.
“This man is now afraid to go to work. He went in today and spoke to his supervisor, and the only reason he is not going to work (is) because he is fearing for his own safety and he thinks, like his family members were the victims, he could be a victim.
“The family are okay but they are traumatised.”
Mr Yakoob said one of the men’s condition has “worsened” since Wednesday night, with a CT scan revealing there is “a cyst on his brain”.
“The main concern for us, for me, is that the family receive justice and this no longer happens again,” the solicitor went on.
“Just imagine a first-time visitor to the UK and they get to see the brutality from the UK police. They will not want to visit the UK again.
“I wouldn’t if I see that sort of brutality by people who were meant to be the protectors of the public, and not aggressors and oppressors.”
Mr Yakoob refused to be drawn on what may have been the spark to the fracas.
Asked why the police had approached the family, he said: “That’s not relevant. The relevant issue right now is the health and the wellbeing of the family."
Mr Yakoob said he had a “long history” with the police himself but added: “We are with policing but we are against people taking advantage of their powers.”
He said he hoped that “honest” police officers would come forward to assist the ongoing IOPC investigation.
In a statement, Mayor of Greater Manchester Andy Burnham said: “The Deputy Mayor and I have now had the opportunity to meet with both the Home Secretary and the regional director of the Independent Office for Police Conduct (IOPC).
“It was agreed that the IOPC investigation now under way will be carried out as swiftly as possible, will involve community stakeholders and will be truly independent.
“The precise arrangements will be set out by the IOPC.
“I hope this provides further reassurance to people that all the right steps are being taken, that all relevant issues will be fully considered and gives people confidence in the process as it moves forward.”
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