Around 180 British troops have been deployed to the English city of Salisbury to aid in the investigation of a nerve agent attack on a former Russian double agent and his daughter, the media reported.
Personnel from the Royal Air Force, British Army and Royal Navy were among those sent to Salisbury on Friday, a Defence Ministry spokesman told CNN on Friday.
Sergei Skripal, 66, and his daughter Yulia, 33, were still hospitalised in "very serious condition" after they were poisoned earlier this week, UK Home Secretary Amber Rudd said as she visited Salisbury on Friday.
The pair -- believed by authorities to have been deliberately targeted -- were found slumped on a bench near a shopping centre on the afternoon of March 4.
Rudd visited several of the sites cordoned off by investigators before heading to Salisbury District Hospital.
Detective Sgt. Nick Bailey, a policeman who also fell ill, is in serious condition, but is "conversing and engaging" with visitors, Rudd added.
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Authorities earlier revealed 21 people had received medical attention in the aftermath of the incident, but only three people were still being treated Friday, reports CNN.
Identifying the source of the nerve agent continues to be central to the probe but so far, Rudd has refused to name any potential culprits.
"We will have to wait until we're absolutely clear what the consequences could be, and what the actual source of this nerve agent has been," Rudd said.
On Friday, Russian Foreign Ministry Sergey Lavrov said Russia was ready to assist "any investigation" but that it was "not necessary to hurl unfounded accusations on TV".
Skripal is considered a traitor in his native Russia after a 2006 conviction for spying for the UK, for which he was sentenced to 13 years in prison, CNN reported.
He arrived in the UK in 2010 as part of a spy swap between the US and Russia, when the two countries exchanged agents on chartered planes on a runway at an airport in Vienna, Austria.
--IANS
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