London found out all the details in the Scripale case

The UK authorities are confident that they have clarified all the details of the assassination attempt and established the whole chain of people allegedly involved in the poisoning in Salisbury.
Origin source
The British authorities are confident that they know "everything that is worth knowing" about the attack on the ex-GRU officer Sergei Skripal, reports The Telegraph, citing government sources.

According to the publication's interlocutors, the GRU agent network, which, according to London, was behind the attack in Salisbury, was discovered and eliminated, and in the coming years the threat from this special service was over. According to sources, the details of the plot are well known, including the chain of people who stood at the head of this assassination, the newspaper writes. At the same time, sources claim that the chain leads to the top leadership of Russia.

At the same time, according to newspaper sources, London fears that Russia is creating a new spy network in the UK, this time with the participation of the Foreign Intelligence Service (SVR). "We are more afraid of what we do not know about the SVR, compared with all that we know about the GRU," the publication quotes the words of one of its government sources.

“If Moscow now allocates more resources to the NER and gives more freedom to work in the UK, which, we believe, is happening, then this causes much more concern because they are a more professional unit,” the second source said.

Sergey Skripal and his daughter Julia were found unconscious on one of the street benches in Salisbury in early March last year. According to the London version, both were poisoned by the “Newcomer” nerve agent. Behind the attack, as the British authorities believe, is Russia and, in particular, the GRU. Moscow denies any involvement.