British police are scouring sections of Salisbury and Amesbury in southwest England, searching for a container feared to be contaminated with traces of the deadly nerve agent Novichok.
More than 100 police officers are hunting for an object that contaminated a British couple who fell ill over the weekend in Amesbury, a small town near the city of Salisbury where former Russian double agent Sergei Skripal and his daughter Yulia collapsed on March 4.
The two new victims -- Dawn Sturgess and Charlie Rowley-- are in critical condition in a hospital.
Police said they had established that the couple were exposed to the nerve agent after "handling a contaminated item” that may have been used in the attempted murder on the Skripals.
It was unclear how the 45-year-old man and the 44-year-old woman came into contact with the nerve agent.
British officials blamed the March poisoning of Sergei and Yulia Skripal on Russia. The Kremlin has denied any involvement.
"It is completely unacceptable for our people to be either deliberate or accidental targets, or for our streets, our parks, our towns, to be dumping grounds for poison," British Home Secretary Sajid Javid told lawmakers on July 5.
Novichok is a military-grade nerve agent developed by the Soviet Union.