Russia's Investigative Committee said on Friday it had opened a criminal investigation into the attempted murder of Yulia Skripal, daughter of former double agent Sergei Skripal, and what it said was the murder of another Russian in Britain.
Yulia Skripal was a Russian citizen, the Investigative Committee in a statement.
It said it was also investigating what it called the murder in Britain of Nikolai Glushkov, 68, an associate of late Russian tycoon Boris Berezovsky.
Russian investigators said in the same statement they were ready to cooperate with their British counterparts.