Sheila Patel saw the attack unfold from her third-floor balcony, as the extremist started shooting on the private beach at the Riu Imperial Marhaba Hotel, leaving 38 people dead.
In a statement read at the inquest on Rezgui’s 30 British victims, Mrs Patel, who was on holiday with her husband, described seeing Rezgui approach a male tourist on a sunbed on the beach at the resort of Sousse.
She said: “He appeared very casual and may even have been smiling.
“The white man got off his bed and the terrorist just shot him.”
Mrs Patel also described a “big woman” who could not run to get away as others fled, and instead tried to hide by climbing over a wall.
“The terrorist shot her and she fell,” Mrs Patel added.
Her evidence was heard during a part of the inquest regarding Christopher and Sharon Bell, from Leeds, who were both shot dead close to the hotel swimming pool.
Mr Bell, 59, and his 54-year-old wife were described as a loving couple who doted on their two grandchildren. The pair, who had two sons and a daughter, lived in a quiet street in the Killingbeck area of Leeds.
Mr Bell was a former bus and taxi driver who worked in the ticket office at Leeds railway station, the inquest heard. Mrs Bell had started as a carer for people with learning difficulties and rose to a management position.
A statement from their family, several of whom were watching via video-link from Leeds, was read in court.
It said: “Both were never happier than when they were surrounded by their family in the midst of the banter shared by them all.
“The icing on the cake for Sharon and Christopher was the arrival of their grandchildren.”
The inquest also heard that a Briton wounded in the terror attack died on his way to hospital after his ambulance sat motionless outside the hotel where it took place for up to 20 minutes before leaving.
James McQuire, 66, was with his wife Ann, 63, on their first holiday away after retiring when Rezgui opened fire. The inquest heard the Glasgow-born couple, who lived in Cumbernauld, North Lanarkshire, were shot near the hotel swimming pool as they tried to flee.
Mrs McQuire died at the scene but her husband, who had lain wounded but conscious next to the body of his wife of 43 years, died later in the back of an ambulance as he was being taken to hospital.
Holidaymaker Carol Harrison, a staff nurse from Aberdeen Royal Infirmary who tended Mr McQuire, said apart from a doctor and the ambulance crew she saw no other medically trained people at the scene before leaving in the ambulance with the wounded Scot - and was told there were no first aid kits available.
She told the hearing at the Royal Courts of Justice in London the ambulance looked more like a “patient transport” vehicle rather than an emergency one, lacking any equipment barring oxygen.
Asked how long it waited outside the hotel she said: “It was 15 to 20 minutes. I asked several times ‘can we go? This man is having trouble breathing, he needs to go to hospital’.”
After the ambulance finally left, she said, Mr McQuire suffered a cardiac arrest.
Mrs Harrison, a nurse for 37 years, told how she and husband Brian, a trained first aider, had gone to the aid of the wounded.
She said she came across “Jim from Cumbernauld” as he lay next to his wife but decided not to move him because he had been shot in the pelvis, fearing the wound, which had stopped bleeding, would restart if she did.
But she said as she comforted him hotel staff came and lifted him onto a sunlounger before taking him to the ambulance.
Judge Nicholas Loraine-Smith, the coroner, asked: “You saw a doctor and you saw some ambulance staff. Apart from them did you see any medically trained people of any sort?”
Mrs Harrison replied: “No.”
In pen portraits, Mr and Mrs McQuire’s son Stuart said they had been robbed of a future retirement after years of hard work.
He wrote: “This was meant to be the first of many holidays, sadly this was not to be. They were taken from us before their time.
“They were both stolen from us in a senseless attack, along with so many. I feel they were just starting a new chapter in their lives where they could spend more time with each other.”
The couple were keen musicians who performed in a band called Tartan Spirits, the inquest heard.
More than 400 people attended their funeral at Abronhill Parish Church, where they had been active members of the congregation, in July 2015.
Mr McQuire was a shipyard engineer and trade union shop steward who spent most of his working life at the Yarrow shipyard and had most recently been a consultant on the Queen Elizabeth Class aircraft carrier project, the inquest heard.
He was a regular churchgoer and captain of the Boys’ Brigade, whose help extended to providing job character references for boys going on to get work as adults.
Mrs McQuire was a lab technician turned medical receptionist whose kindness extended to delivering prescriptions to people who could not pick them up.
She had stood out as an excellent singer at church, her son said, and quietly supported her husband’s work with The Boys’ Brigade.
Stuart McQuire wrote that since the attack his wife Nicola had given birth to his parents’ first grandchild, a girl who had been named Lily Ann in memory of her grandmother.
He said Lily had “brought joy to the family after so much tragedy”, but added: “It’s heartbreaking for the family that they have missed out on meeting Lily and they will not be able to watch her grow.”
The inquest, which is due to last between six and eight weeks, continues.