Tests Suggest Aleksei Navalny Was Poisoned, German Doctors Say

BERLIN — Tests on Aleksei A. Navalny, the prominent Russian dissident who fell ill on a flight to Moscow last week, have revealed indications of poisoning but his life is not in danger, the hospital where he was being treated said in a statement on Monday.

“The clinical findings indicate intoxication by a substance from the group of cholinesterase inhibitors,” the doctors at Charité hospital said. “The specific substance has not been identified so far, and a further wide-ranging analysis has been initiated.”

The effect of the toxin “has been proven several times and in independent laboratories,” the statement said.

Mr. Navalny remained in an induced coma in stable condition, but his life was not in danger, according to the statement. The doctors said that although it was too early to tell what the lasting effects would be for Mr. Navalny, “the possibility of long-term effects, particularly those affecting the nervous system, cannot be excluded.”

He was taken to Berlin on Saturday, more than 48 hours after he fell ill and his flight to Moscow was forced to make an emergency landing in Omsk, Siberia. His family and supporters organized an air ambulance to bring him to Germany, where Chancellor Angela Merkel had offered him access to medical care.

Ms. Merkel’s government enjoys strong economic and cultural ties to Russia but has not shied from criticizing policies of President Vladimir A. Putin.

Even before Mr. Navalny arrived in Berlin, the German government appeared to be taking extra precautions to ensure his safety. Minutes before landing, his plane was rerouted from Schönefeld Airport to Tegel Airport, and the ambulance that brought him from the tarmac to the Charité hospital was escorted by the police. A police van and several officers have been stationed outside the hospital’s main entrance since Saturday.

“It was clear that after he arrived here, security measures had to be put in place,” Ms. Merkel’s spokesman, Steffen Seibert, told reporters on Monday, before the statement from the hospital. “We are dealing with a patient who appears, with a certain level of probability, to have been the target of a poisoning attack.”

“Unfortunately there a one or more examples of such poisonings in recent Russian history,” Mr. Seibert added.

The Russian security services are suspected of having used a range of poisons to eliminate opponents, although Russian officials have consistently denied any evidence of poisoning. On Monday, doctors in Omsk who treated Mr. Navalny last week again denied finding any evidence of toxins in his system.