A 33-year-old woman discovered next to a former Russian double agent has been identified as his daughter.
Sergei Skripal, a 66-year-old former spy and his 33-year-old daughter, Yulia, were found on Sunday unconscious on a bench outside a shopping center in the English city of Salisbury, after exposure to what police said was an unknown substance.
Skripal was arrested in 2004 by Russia's Federal Security Service (FSB) on suspicion of betraying dozens of Russian agents to British intelligence. He was sentenced to 13 years in prison in 2006 after a secret trial.
He was pardoned in 2010 by then-President Dmitry Medvedev as part of a swap to bring 10 Russian agents held in the United States back to Moscow.
The incident recalls the poisoning of ex-KGB agent Alexander Litvinenko with radioactive polonium-210 in London in 2006, a killing which a British inquiry said was probably approved by President Vladimir Putin.
The Kremlin said on Tuesday it was ready to cooperate if Britain asks it for help in investigating Skripal’s condition.
Calling the incident "a tragic situation," Putin spokesman Dmitry Peskov said the Kremlin did not have information about what had happened.
"We don’t have information about what the reason [for the incident] could be, what this person was doing, and what it could be linked to," he said.
Includes reporting by Reuters.