AP Photo
A police tent is framed by police tape covering the the spot where former Russian double agent Sergei Skripal and his daughter were found critically ill Sunday following exposure to an "unknown substance" in Salisbury, England, Wednesday, March 7, 2018. Britain's counterterrorism police took over an investigation Tuesday into the mysterious collapse of the former spy and his daughter, now fighting for their lives. The government pledged a "robust" response if suspicions of Russian state involvement are proven. Sergei Skripal and his daughter are in a critical condition after collapsing in the English city of Salisbury on Sunday. (AP Photo/Matt Dunham)