TWO British citizens are critically ill after they were exposed to Novichok, the same nerve agent that struck down a former Russian agent and his daughter in March, Britain’s top counter-terrorism officer said Wednesday.

The pair, a local 44-year-old woman and a 45-year-old man, were hospitalized after being found unwell Saturday in Amesbury, just miles away from Salisbury where ex-double agent Sergei Skripal and his daughter Yulia were attacked in March.

“I have received test results from Porton Down (military research center) which show that the two people have been exposed to the nerve agent Novichok,” Neil Basu, Britain’s most senior counter-terrorism officer, told reporters.

Britain has accused Russia of poisoning the Skripals with Novichok — a nerve agent developed by the Soviet military during the Cold War — in what is the first known offensive use of such a chemical weapon on European soil since World War Two.

Russia has denied any involvement in their poisoning.

U.K. counter-terrorism police are now leading the investigation, though Basu said it was unclear how the two people came into contact with the nerve agent or whether they had been specifically targeted.

“I don’t have any intelligence or evidence that they were targeted in any way,” Basu said. “There is nothing in their background to suggest that at all.”

Amesbury is located seven miles (11 km) north of Salisbury, where Skripal — a former colonel in Russian military intelligence who betrayed dozens of agents to Britain’s MI6 foreign spy service — and his daughter were found slumped unconscious on a bench March 4.

Around 100 counter-terrorism officers are working on the case and police have cordoned off at least five different areas, including a park and a property in Salisbury, as well as a pharmacy and a Baptist church community center in Amesbury.

The March attack prompted the biggest Western expulsion of Russian diplomats since the Cold War as allies in Europe and the United States sided with U.K. Prime Minister Theresa May’s view that Moscow was either responsible or had lost control of the nerve agent.

Mystery surrounds the attack and the motive is unclear, as is the logic of using such an exotic nerve agent which has overt links to the Soviet military during the Cold War.

Russia, which is currently hosting the soccer World Cup, has denied any involvement in the March incident and suggested Britain had carried out the attack to stoke anti-Moscow hysteria.

Moscow also hit back by expelling Western diplomats, questioning how Britain knows that Russia was responsible and offering rival interpretations, including that it amounted to a plot by British secret services. Russian officials questioned why Russia would want to attack an aging turncoat who was pardoned and then traded in a Kremlin-approved 2010 spy swap.

(SD-Agencies)