According to a statement released on Thursday by a Siberian branch of Russia’s Interior Ministry, investigators in the region are working on “establishing all the circumstances of the incident”, conducting forensic studies and collecting items “that may have probative value”.
Mr Navalny, an opposition politician and corruption investigator who is one of President Vladimir Putin’s fiercest critics, fell ill on a flight back to Moscow from Siberia last Thursday and was taken to a hospital in the Siberian city of Omsk after the plane made an emergency landing.
Over the weekend, he was transferred to the Charite hospital in Berlin, where doctors found indications of “cholinesterase inhibitors” in his system. But a specific substance has not yet been identified.
Found in some drugs, pesticides and chemical nerve agents, cholinesterase inhibitors act by blocking the breakdown of a key chemical in the body, acetycholine, which transmits signals between nerve cells.
Mr Navalny’s allies insist he was deliberately poisoned and say the Kremlin was behind it, but Moscow officials have branded the accusations “empty noise”.
Mr Navalny’s team submitted a request to Russia’s Investigative Committee, demanding authorities launch a criminal probe on charges of an attempt on the life of a public figure, but officials had appeared reluctant to start an investigation.
Kremlin spokesman Dmitry Peskov said on Monday he sees no grounds for a criminal case until the cause of the politician’s condition is fully established.
The Interior Ministry’s statement on Thursday did not clarify when the preliminary probe – an inquiry to determine whether a criminal investigation should be launched – started.
The announcement about the inquiry comes after multiple Western and European officials – including German Chancellor Angela Merkel, British Prime Minister Boris Johnson and US Secretary of State Mike Pompeo – called on Russia to start a full and transparent investigation into Mr Navalny’s condition.
On Wednesday night, the politician’s illness was discussed in a phone call between Mr Putin and Italian Prime Minister Giuseppe Conte.
According to the Kremlin, Mr Putin pointed out on the call that “premature and unfounded accusations” are unacceptable and he underscored Russia’s “interest in a thorough and objective investigation of all the circumstances of the incident”.
