British counter-terror police are aiding a probe into what caused the critical illness of a former Russian double agent in Salisbury.
Metropolitan Police assistant commissioner Mark Rowley confirmed that his specialists were supporting the investigation into why Sergei Skripal fell ill at The Maltings shopping centre on Sunday afternoon.
The Kremlin has denied suggestions Russia poisoned the 66-year-old, who was convicted in the country of spying for MI6 in 2006. It was alleged that he disclosed the names of several dozen Russian agents working in Europe.
When asked about speculation in the British press that Russia had been involved, Kremlin spokesman Dmitry Peskov said: “It didn’t take them long.”
Mr Skripal’s illness was “a tragic incident”, he added.
The Kremlin has said Moscow is “always open for cooperation” regarding the British investigation, which Mr Rowley described as a “very unusual case”.
“Clearly it’s a very unusual case and the critical thing is to get to the bottom of what has caused this incident as quickly as possible,” he told BBC Radio 4’s Today programme.
“As you would expect, the specialist resources that sit within the counter-terrorism network that I coordinate across the country and other partners are working with Wiltshire Police to get to the bottom of that as quickly as possible.”
He told BBC Radio 4’s Today programme: “If you look back at other cases like (Alexander) Litvinenko, if necessary we will bring that investigation into the counter-terrorism network.
“At the moment the key is, though, to get to the bottom of what caused this.”