SALISBURY, England – The Latest on developments surrounding the former Russian spy found critically ill in the southern England town of Salisbury (all times local):
British counter-terror specialists are supporting police in Salisbury after a former Russian spy fell critically ill after exposure to an "unknown substance."
Metropolitan Police assistant commissioner Mark Rowley told the BBC that the case is unusual and that it is critical to determine what happened as soon as possible.
The incident involving Sergei Skripal, 66, immediately drew parallels to the death of former Russian agent Alexander Litvinenko, who was poisoned with radioactive polonium 11 years ago in London.
A woman was also found unconscious Sunday afternoon in Salisbury, about 90 miles (145 kilometers) west of London.
When asked about a series of suspicious Russian-linked deaths in Britain, Rowley said "we have to remember that Russian exiles are not immortal, they do all die and there can be a tendency for some conspiracy theories.
"But likewise we have to be alive to the fact of state threats as illustrated by the Litvinenko case."
The Kremlin says Russia has not been approached to help in an investigation over how and why a former Russian spy was found critically ill in a shopping mall in a town in southern England.
British media have identified him as Sergei Skripal, 66, who was convicted in Russia on charges of spying for Britain and sentenced in 2006 to 13 years in prison.
Skripal, who is said to have suffered exposure to an "unknown substance" was freed in 2010 as part of a U.S.-Russian spy swap. A woman was also found unconscious Sunday afternoon in Salisbury, about 90 miles (145 kilometers) west of London.
Dimitry Peskov, President Vladimir Putin's spokesman, said Tuesday that there has been no request for help but that "Moscow is always ready to cooperate."