A major incident was declared in Salisbury Monday following the quarantine and disinfecting of a shopping area and hospital in Salisbury, England, with a former Russian military colonel and one other left in critical condition.

Sergei Skripal, a 66-year-old retired Rusian military intelligence colonel who was convicted of selling state secrets to Britain during the 1990s but later brought to Britain as part of a spy prisoner swap has been revealed as one of those taken seriously ill on Sunday, reports the BBC.

Two people were taken to hospital Sunday after falling unconscious at the Maltings shopping centre after exposure to what was then described as an unidentified substance. Police later said they suspected the substance was a highly powerful synthetic opiate called fentanyl, but this remains unclear.

Following the incident at the shopping centre, Salisbury hospital A&E was evacuated, possibly because of contamination from the two injured individuals. A number of other people have since been treated.

Although a high ranking officer in the Russian military, Skripal was also working as an intelligence asset for Britain’s MI6 foreign intelligence agency in the 1990’s and it was claimed by Russian prosecutors that MI6 had paid him £100,000 for military secrets. The other victim, a woman in her 30’s, has not been named.

We received a call at approx. 4.15pm yesterday (4 March 2018) regarding concern for the welfare of a man and a woman in The Maltings, Salisbury. They were taken to Salisbury District Hospital & are being treated for suspected exposure to an unknown substance. #Salisbury — Wiltshire Police (@wiltshirepolice) March 5, 2018

The fire brigade was called to decontaminate the scenes in both cases, with fire officers wearing hazmat-suits wrapping material in “several protective layers” before preparing to destroy it by burning, reports the Salisbury Journal.

Two specialist ambulance vehicles marked ‘Incident Response Unit’ were dispatched to the scene as green tents were set up at the entrance of Salisbury hospital. A&E Staff were evacuated to a nearby building to establish a triage centre while the facility was closed for decontamination.

A spokesman for the hospital said it is “currently dealing with a major incident involving a small number of casualties, with a multi-agency response”, and less than ten people are understood to have been treated. The hospital had re-opened by Monday afternoon.

Police said:

“Police received a call at approximately 4.15pm yesterday regarding concern for the welfare of a man and a woman in The Maltings, Salisbury.

“They were taken to Salisbury District Hospital and are being treated for suspected exposure to an unknown substance. They are currently in a critical condition.

“At this stage it is not yet clear if a crime has been committed and a multi-agency response has been co-ordinated.

“Police are carrying out a full investigation and working with partner agencies, to clarify the exact circumstances.

“At this stage, Wiltshire Police does not believe there is any risk to the wider public.”

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