Updated

British media say a former Russian spy is in critical condition after coming into contact with an "unknown substance."

Authorities did not identify the man, but the Press Association and other British media identified him Monday as Sergei Skripal, 66, who was convicted in 2006 on charges of spying for Britain and sentenced to 13 years but was freed in 2010 in a U.S.-Russian spy swap.

His identity was first disclosed by the BBC.

Following his arrest in Moscow in December 2004, Skripal confessed to having been recruited by British special services in 1995 and was feeding them information about Russian agents in Europe, receiving over $100,000 for his services.