A Marks and Spencer security guard is facing a long jail sentence after he was found guilty of killing a shoplifter he suspected of stealing meat.
The jury took just four hours of deliberation today to convict Sabeur Trabelsi of manslaughter.
They had earlier heard how the security guard, 44, landed a "knockout blow" to the head of homeless Jason Page outside the supermarket in Lower Earley, Reading, Berkshire, on March 31 last year.
Mr Page fell to the ground, hitting his head so hard he never recovered from his injuries and died in hospital.
After he was arrested, father-of-three Trabelsi tried to claim that 51-year-old Mr Page fell over because he was drunk and that was why he hit his head.
He denied throwing a punch at him.
However, CCTV footage seen by the jury showed otherwise and they convicted him of manslaughter and perverting the course of justice.
The former conviction means the guard, who was not employed by M&S and supplied to the store on temporary basis by a third part security company, could be jailed for up to eight years.
Store manager, Elliot Cripps, who followed Trabelsi out of the shop as he chased Mr Page, was cleared of perverting the course of justice and walked free from Reading Crown Court.
Judge Amjad Nawaz rejected a plea by Trabelsi's defence counsel for him to be granted bail "to put his affairs in order" before being jailed and he was sent straight to the cells.
He will be detailed at Bullingdon Prison in Bicester pending sentencing on June 12.
During the prosecution summing up of the case, it was revealed that Trabelsi, from Kings Road, Reading, had told police in one of several interviews: "I was frustrated, I know I shouldn't have done it."
The jury of eight men and four women retired today to consider whether Trabelsi was guilty.
They heard that the fatal punch happened on Trabelsi's last working day for the store.
He had been hired to work at the supermarket after a spate of thefts of expensive meat and alcohol.
Thirty minutes before the shop was due to close, the guard chased Mr Page outside after he and an accomplice were seen on CCTV "brazenly" filling up a bag with expensive meat and grabbing a box of Moretti beer on their way out.
The jury was told Trabelsi carried on chasing Mr Page towards the nearby BP garage on Chalfont Way, and Mr Cripps followed behind in an attempt to grab back the bag of meat.
CCTV played to the jurors showed Mr Page being wrestled to the ground as Mr Cripps manages to get the meat back from him.
When Mr Page got back on his feet, Trabelsi delivered a "knockout blow", causing him to fall backwards and crash onto the pavement.
He died a short time after from his injuries.
In evidence, Trabelsi told jurors Mr Page had threatened to stab him with a needle when he landed the punch, which he also argued was instead a slap.
Summing up the prosecution case, Mr Ward-Jackson told jurors yesterday: "He (Trabelsi) had pent-up anger. He was angry and wound up, or to use his words - frustrated."
He said his revelation to police was a "rare moment" where he revealed the reason for his crime.
"Which is anger or frustration and if that is right, this is not a case of self-defence but a blow committed on the spur of the moment aimed in anger," he said.
Trabelsi's counsel, Felicia Davey, told jurors: "Was it necessary for Trabelsi to defend himself? On the evidence we submit, how could there be any other conclusion other than 'yes it was'
"We go on to consider the second stage - was what he did reasonable? Knowing that tragically it is the head hitting the floor that does the damage and knowing that tragically Mr Page would have hit the floor much harder and faster than usual [because he had alcohol in his system].
"Again we say how could there be any other conclusion than 'yes'?
"We say that the fact he didn't mention the slap to the police was not for any bad reason - certainly not to pervert the course of justice."
