The British government held another top-level security meeting on March 10 to discuss the poisoning of a Russian ex-spy and his daughter with a nerve agent.
Home Secretary Amber Rudd said after the meeting it was still "too early" to say who was behind the poisoning of Russian double agent Sergei Skripal and his daughter Yulia, who both remain in critical condition.
The March 4 attack on Skripal, 66, and Yulia, 33, in the southern English city of Salisbury is being treated as attempted murder.
Rudd said the investigation has involved more than 250 counterterrorism officers. She said more than 240 pieces of evidence have been collected and 200 witnesses have been identified. Around 180 troops, including chemical warfare experts, have been deployed in Salisbury after investigators requested specialist assistance.
Police said Skripal and his daughter were poisoned with a nerve agent but have refrained from specifying which one.
Meanwhile, Skripal continued to provide Western intelligence agencies with information after arriving in Britain as part of a spy swap in 2010, media are reporting.
The Financial Times and other British news outlets, citing British security sources, reported on March 9 that Skripal continued to discuss Russian intelligence capabilities with Western agencies, although his value as a source "quickly faded."
“He was useful for a limited period,” a senior security source who asked not to be identified told The Financial Times, which cited Skripal's continued cooperation with the West as a possible motive for his poisoning.
Skripal, a retired Russian military intelligence colonel, was convicted by a Moscow military court in 2006 of "high treason" for passing the identities of Russian intelligence agents to Britain's Secret Intelligence Service, or MI6, in return for $100,000. He was one of four Russian prisoners released in 2010 in exchange for 10 Russian sleeper agents.
“While it wasn’t spying, there was an ongoing use” after Skripal's release in 2010 for information he provided to Western intelligence services, particularly as they trained their own spies, a second official told The Financial Times.
"This is what the Russian priorities were; this is how they infiltrate the West, how they recruit, how to counter intelligence...these types of things. Especially as we train people up, that was an ongoing use,” the official said.
The security officials told The Financial Times and other media that Skripal may have given occasional presentations and talks to U.K. military and intelligence personnel after arriving in Britain.
The security officials told The Financial Times, however, that reports Skripal continued to work in recent years for private companies that do work for British military and intelligence agencies were not credible.
The news about Skripal's activities during his exile in Britain came as Britain's Ministry of Defense said some 180 troops, including some chemical experts, have been sent to Salisbury to remove ambulances and other objects involved in the incident.
Counterterrorism police, who are leading the investigation, said "the public should not be alarmed," adding, "Military assistance will continue as necessary during this investigation."
British authorities have called the poisoning an "appalling and reckless crime" that they are treating as "attempted murder" and have said they will respond appropriately if evidence shows Moscow was behind the incident.
Moscow has denied involvement and asserted that anti-Russian hysteria is being whipped up by the British media.