A WOMAN has told how she and her husband fell ill at a Salisbury restaurant, sparking fears they had fallen victim to Novichok poisoning.

Witnesses described a scene like "Armageddon" as police and emergency services, some wearing protective suits, rushed to the scene on Sunday evening as a major incident was declared.

Russian-born Anna Shapiro, 30, said she had been dining at the Prezzo Italian restaurant with partner Alex King, 42, when he began to feel unwell towards the end of the meal.

Speaking to The Sun, the model said her husband went to the toilet and she grew concerned when he did not return after 15 minutes.

"I headed up and saw him lying on the floor near the sinks," she said.

"I ran downstairs for help. I was panicked."

Soon after when Ms Shapiro went to raise the alarm, she too began to feel unwell, the paper said.

Emergency services were called to the city centre restaurant at 6.45pm and the pair were taken to Salisbury District Hospital.

Wiltshire Police said inquiries were ongoing into what caused them to become unwell, although they have ruled out exposure to Novichok or a similar poison.

"Tests have confirmed that the two patients who fell ill in Prezzo restaurant in Salisbury on Sunday evening were not exposed to any kind of nerve agent," the force said.

"Following test results, at this stage, this is not being treated as suspicious.

"Therefore, at this stage, we are not linking their illness to the recent poisonings in Salisbury and Amesbury."

The incident came amid heightened tensions in Salisbury in the wake of the poisoning of former Russian spy Sergei Skripal and his daughter, Yulia, in March.

The Prezzo is a short walk from Queen Elizabeth Gardens, which was until recently closed off after 44-year-old Dawn Sturgess was fatally poisoned by the nerve agent in June.

Amanda Worne was at the restaurant when the drama began on Sunday.

She described how a "beautiful blonde" had gone up to the restaurant's toilet before returning "hysterical".

"(She said) 'Oh my God, we need an ambulance, we need an ambulance, someone help we need an ambulance'," Ms Worne told the Press Association.

Paramedics arrived and donned protective clothing after discovering the two patients.

"The next thing it was all carnage, it was armageddon, there were sirens, ambulances," she said.