Counter-terrorism police are investigating after two people in Wiltshire have been left in a critical condition after being exposed to a mystery substance.

Named locally as Charlie Rowley, 45, and Dawn Sturgess, 44, the pair were found unconscious at a property in Muggleton Road, Amesbury on Saturday.

The property is around eight miles from where former Russian spy Sergei Skripal and his daughter Yulia were poisoned with a nerve agent in March.

However, it's not thought that the individuals are linked in any way to Russia or to the Skripals.

Police outside a block of flats on Muggleton Road in Amesbury. Credit: PA images

What do we know so far?

  • A man and and a woman from Amesbury are in a critical condition in Salisbury District Hospital

  • It's believed that one of the last places they were seen in public was a family fun day at Amesbury Baptist Centre on Saturday afternoon

  • A number of locations have been cordoned off

  • Public Health England say they don't believe there to be a "significant health risk" to the wider public

  • Salisbury District Hospital is "open as usual"

A number of scenes, believed to be the areas they visited in the period before they fell ill, remain cordoned off in and around the Amesbury.

Five locations have been cordoned off by police. Credit: PA images

Where are the police cordons?

  • Queen Elizabeth Gardens in Salisbury

  • A property at John Baker House, Rolleston Street, Salisbury

  • A house on Muggleton Road, Amesbury

  • Boots the Chemist, Amesbury, Stonehenge Walk, Amesbury

  • Amesbury Baptist Centre on Butterfield Drive, Amesbury

Deputy Chief Constable Paul Mills speaking to the media in Amesbury. Credit: PA images

What are Wiltshire Police saying?

Wiltshire Police initially thought that the couple had taken contaminated crack cocaine or heroin.

Further tests led them to declare it a major incident.

It is understood that tests are being carried out on the substance at theGovernment chemical weapons research laboratory at Porton Down.

They say that at this stage it is not yet clear if a crime has been committed.

Given the recent events in Salisbury, officers from the counter-terrorism network are working jointly with colleagues from Wiltshire Police regarding the incident in Amesbury.

Metropolitan Police, who lead the national counter-terrorism network
Amesbury Baptist Centre - one of the last places they were seen in public. Credit: PA images

What about the Government?

A meeting of the Government's Cobra emergencies committee took place on Wednesday morning to discuss the events.

A Downing Street spokesman said: "This is an incident which understandably is being treated with the utmost seriousness.

"Ministers and the Prime Minister are being kept updated and there was ameeting this morning of officials to receive updates on the facts of thesituation."

Police are trying to establish what has happened. Credit: PA images

Police say they are very aware of the public interest in this investigation and their concern.

They have set up two dedicated phone numbers for anyone withconcerns relating to this incident.

Those numbers are 0800 092 0410 or 0207 158 0124.