Security guards for European football club Manchester United have been accused of calling a Black teenage employee at the stadium a "slave" and assaulting him in broad daylight.

Kamarl Nelson, a 19-year-old cleaning employee working at Old Trafford soccer stadium in Greater Manchester, told the BBC and The Guardian that he was on his way to work when security guards for the team refused to let him in. They repeatedly accosted him with racial slurs before fracturing his eye socket and bruising his ribs.

Nelson had spent six months working for Arc Hospitality, a company the stadium pays for cleaning services, and he was a ball boy with the team for three years after playing for the club's youth development team. 

However, on February 27, he showed up for work and was stopped by a security guard who claimed Nelson couldn't have worked there. The security guard's supervisor came over and joined in harassing Nelson. They searched him and allegedly said "I'm surprised I didn't find a knife.'"

After further harassment, Nelson called over three Greater Manchester police officers and asked them for help. The officers then joined the security guards in belittling Nelson, searching him without cause and telling him he wouldn't be able to enter the building with his bag. 

"I can buy and sell you. You're a slave. At least I have my own last name," one of the security guards said.

The police told Nelson he would have to leave or be arrested, so he called his supervisor at Arc Hospitality to ask that they let him in. After 15 minutes, he entered the building and was confronted by the security guards again, who continued their verbal abuse even after Nelson called over other supervisors. 

Eight security guards then grabbed Nelson by the neck, punched him in the stomach and threw him around, only stopping when the police officers returned, according to a statement from human rights group Kids of Colour. A manager from Arc Hospitality sided with the security guards and told Nelson to go home.

The security company, Controlled Solutions Group, said Nelson was lying and making the entire thing up. Manchester United released its own statement denying any involvement.

Five different sources spoke to The Guardian about what they saw during the incident. 

“I heard one of the security guards say, ‘You work here?’ and ‘You don’t f**king work here, and if you do, what do you do – make f**king cups of tea or clean the boots or what?’ I said to the security guard it was out of order saying that … and he went: ‘F**k off you, mind your own business,’” said 53-year-old Tom Tatler, who also said he heard the guards use a racial slur toward Nelson.

Tatler confirmed Nelson's account about the police as well, telling the newspaper he tried to alert police about what was happening to Nelson but was told to "mind his business."

“It was getting a bit heated but I wouldn’t say Kamarl was the aggressor – it was the other three guys. From what I saw, it was a bit heavy-handed,” said 48-year-old season-ticket holder Mat Shufflebotham.

Harry Robinson, 19, Calum Young, 21, and Wendy Smith, 59, all said they saw the security guards surrounding and attacking Nelson that day.

“It looked like they were trying to take his bike off him. He [Nelson] didn’t seem to be doing that much wrong. He seemed a little distressed. He was by himself against six or seven [guards] so I would say they seemed to be the aggressors,” Robinson said in an interview. 

The situation was first publicized by Kids of Colour on Twitter and Nelson's mother, Donna James, who told news outlets that the response from the team and the security company was unacceptable.

“I thought once [Manchester United] recognized his affiliation to the club they would have come forward and might even have come round and seen us as a family. They might have had a chat with Kamarl and offered him personally some reassurance that they were looking into it. But none of that has happened. That’s really disappointing because Kamarl has really fond memories of being at United from being young and doing things there. He really enjoyed his time as a ballboy there. It’s really hurtful that they haven’t put more of a human response to it,” James said.

Greater Manchester police said they were looking over video footage from the team and were still investigating the case. Since being shamed online, Manchester United has spoken with Nelson and his family.