The British police officer announced that 66-years-old Sergei Skripal, who spies on behalf of the United Kingdom while serving in the Russian military intelligence, found unconscious with his 33-years-old daughter, have been exposed to a chemical attack that affects their nervous system.

"This is being treated as a major incident involving attempted murder by administration of a nerve agent," said London Police Department Deputy Director Mark Rowley.

Former Russian agent Skripal and his daughter Yulia had been found unconscious in a shopping mall in Salisbury of England on Sunday night.

Meanwhile, Mark Rowley said the police officer who was first to the spot where Skripal was found in Salisbury on Sunday afternoon was "seriously ill" in hospital. His condition had deteriorated, Rowley said.

it was stated that the police, who first arrived at the scene, were also affected by the chemical substance, continued treatment in the intensive care unit and maintained the seriousness of the situation.

British Foreign Secretary Boris Johnson said in parliament that they would respond "strongly" if any state's responsibilities were detected.

"The British authorities and the security forces must immediately intervene to prevent the attempts to make Russia look like the devil," warned the Russian authorities said, referring to the official statement from the United Kingdom.

Russia argues that the accusation of Moscow in the poisoning of the former Russian agent and her daughter was wrong and that this accusation was made to harm the relations between England and Russia.

Sergei Skripal: Swapped spy

Sergei Skripal has been on secret duty in Europe for MI6, the UK's foreign intelligence service.

Russia has announced that Skripal has identified Russians agents in Europe to the British foreign intelligence service MI6 and that he has received $ 100,000 in cash for information leaked to British intelligence since the 1990s.

Skripal, 66, was sentenced to 13 years in Russia in 2006 for alleged spying for the UK.

In July 2010, Skripal was one of four prisoners released in the Austrian capital Vienna by Moscow in exchange for 10 Russian spies arrested by the U.S. (ILKHA)