On Thursday, U.K. officials said that nearly two dozen people were being treated in the suspected nerve agent attack on a former Russian spy and his daughter.

Sky News noted that three people remain in the hospital from the suspected attack including the former Russian spy Sergei Skripal, his daughter Yulia Skripal, and police sergeant Nick Bailey.

“Multiple people have been treated, around 21 people, including the man and the woman found on the bench,” said Kier Pritchard who is the acting chief constable of Wiltshire Police. “A number of those have been through the hospital treatment process, they are having blood-tests, support and advice.”

Assistant Commissioner Mark Rowley, head of Counter Terrorism Policing, said that scientists in the British government have identified the nerve agent used, but they are not releasing that information at this time.

“This is being treated as a major incident involving attempted murder, by administration of a nerve agent,” Rowley said. “Having established that a nerve agent is the cause of the symptoms … I can also confirm that we believe that the two people who became unwell were targeted specifically.”

The BBC’s Richard Galpin, who was formerly based in Moscow, said that nerve agents are not something that terrorist and organized crime groups are usually capable of making: ​

Instead, it is usually manufactured by specialist laboratories under the control of governments — and that inevitably means suspicion will now be very much focused on Russia.

Not only does it have a track record of using poisons to assassinate its enemies, there is also a motive in the case of Sergei Skripal.

As a military intelligence officer in Russia, he betrayed his country by providing information to MI6, reportedly revealing the identities of Russian agents in Europe. And Russian President Vladimir Putin has in the past indicated that traitors deserve to die.

Foreign Secretary Boris Johnson told British lawmakers that if Moscow was behind the suspected attack on Skripal that “the government would act — possibly downgrading England’s participation in this year’s soccer World Cup in Russia,” Fox News reported.