Kyle Spencer, 19, was grabbed by the neck and dragged out of the John Lewis branch in Westgate, Oxford, on August 5.
The new father, from Oxford, was shopping for baby clothes with his two sisters ahead of the arrival of his firstborn child when he was “assaulted” by the security guard.
Security were then called by staff to reports of disruptive behaviour, they say, and all three were asked to leave.
One of his sisters filmed what happened next as Mr Spencer was hauled out of the shop. “I physically couldn’t breathe," he said. "It was absolutely terrifying.
"He had my neck so tight that I thought I was going to die. For a good week or so after it happened I was scared to go into town again.
“My sisters were in absolute distress. No child should have to see their big brother get attacked like that.
“He was full of anger. I thought he would never let go.”
Mr Spencer says the guard, who has since lost his job, became aggressive when he asked to see his ID badge because his shorts and polo shirt attire “didn’t look like” that of a John Lewis staff member.
"To me he just looked like a normal person in normal clothes. He refused to show me his badge and started to get angry about it," he said.
"I didn’t try to cause an argument or try to be awkward. He asked us to leave but when we were talking he pushed me twice.”
Video footage then shows the guard spin him around and grab him by the neck.
After dragging Mr Spencer out of the store the guard continues to hold Kyle around the neck region, while his sisters can be heard screaming as their brother is tackled to the floor.
He was left with neck pain and bruised ribs and was diagnosed by A&E doctors with a sprain and whiplash, he says.
After reporting the incident to John Lewis directly, on August 22, he received a written apology from the guard the following day in which he is accused of using abusive and threatening language - a claim he denies.
John Lewis say they are “appalled” by the incident and have confirmed the guard no longer works for the company.
A spokesperson for the company said: “We were shocked and appalled to hear of this incident in our Oxford shop and have apologised to the customer.
“This is not what we would expect from anyone who works for us and we can confirm that this individual is no longer employed by John Lewis & Partners.
“We've subsequently conducted an internal investigation and supported the Police with their enquiries.”
Thames Valley Police said: "Thames Valley Police received a report of an assault which took place in Queen Street, Oxford at around 4pm on August 5.
"No arrests have been made. A 52-year-old man received an adult restorative disposal in relation to this incident."
SWNS contributed to this report
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