Speaking about Diatta’s behaviour around displays of watches including Rolexes and Breitlings, Prothero said: “He demanded three free watches from the store in a very aggressive manner.
“His behaviour seemed strange, very bizarre. He wanted to take pictures of the watches and wanted to have three as a reward.
“He then shouted, ‘you are a racist’ three or four times. I opened the door for him to leave and he then tried to grab my face mask. Then he attacked me.”
It was then that he and a male shopper restrained Diatta. Prothero suffered cuts and bruising to his face in the attack.
He added that he did not hear Diatta say that he could not breathe.
Pathologist Dr Peter Cooper performed a post-mortem examination on Diatta and said he had died from a combination of existing heart disease and high blood pressure and “the effect of being restrained”.
He said it was his opinion that the pressure placed on Diatta while he was being restrained would have had been a “significant” contributory factor in his death.
He added: “I don’t think there’s any doubt about that, and I think in a significant way.”
He said that if pressure had been placed on Diatta’s chest while he was face down, he would not have been able to breathe properly and this would potentially lead to asphyxia.
The inquest heard that Diatta had bipolar disorder, asthma, diabetes and high blood pressure.
A York Street Ranger said he and a colleague were also involved in an altercation with Diatta just before the incident at the store.
They were approached by Diatta, who aimed verbal abuse at them and “squared up” before walking off towards the jewellers.
After his death Diatta’s family said he was “a gentle giant, who was kind and generous and loved by all who met him”.
They said: “Sam was half-Senegalese and his family in Senegal meant the world to him. He was a keen sportsman and supported both the England and Senegal football sides. He also played for York RI rugby team.
“Sadly, in his later teenage years Sam developed mental health issues which stayed with him throughout his life.
“He had a strong Christian faith and with two others led the Christian Union at York College.”
Four men who were arrested in connection with Diatta’s death did not face any further action following a police investigation.
The inquest continues.
