Russian Lawyer at Centre of Poisoning Investigation

Russia's leading human rights lawyer is at the center of an investigation by French police after claiming she had been poisoned by a suspicious substance found hidden in her car.

Detectives in the town of Strasbourg were examining whether Karinna Moskalenko - the country's most prominent defender of Kremlin opponents - had been deliberately poisoned.

Moskalenko said on Monday her husband discovered "large" quantities of a mercury-like substance hidden under her car seat. Moskalenko had been due yesterday to attend the Moscow trial of three men accused of involvement in the murder of the crusading Russian journalist Anna Politkovskaya. Politkovskaya, a fierce critic of Vladimir Putin, was shot dead two years ago outside her Moscow flat. Two Chechen brothers, Dzhanrail and Ibragim Makhmudov, have been charged with carrying out surveillance on Politkovskaya. A former police officer, Sergei Khadzhikurbanov, is accused of giving them technical help.

But the trial was overshadowed by Moskalenko's non-appearance. A champion of victims of torture in Chechnya, she represents many of Putin's most high-profile enemies. These include Mikhail Khodorkovsky, the oligarch Putin jailed in 2003, and the opposition leader and former chess champion Garry Kasparov.

Moskalenko said her husband, a chemist, stumbled across the deadly substance while cleaning the family car. She and her family had been suffering from severe headaches, giddiness and nausea. The illness prevented her from flying back to Russia for yesterday's trial, she said.

"When we got to the car we realised something was not normal. The only solution was to call the French police. The car was always locked; nobody should be able to open it," she told France 24. "The exact nature of the act is not clear. Was the intention to provoke or to harm us, to poison me? Those who did this clearly intended to keep me unaware of the presence of the substance."

Yesterday Moskalenko's assistant, Valentin Moiseev, told the Guardian that the lawyer was awaiting the results of toxicology tests from a Strasbourg clinic. She was still feeling groggy, he said, adding: "She's feeling pretty sick."

Mercury is an element that occurs naturally. But exposure to high levels can damage the brain, heart, kidneys, lungs and nervous system.

Police in Strasbourg said a preliminary investigation had been launched into Moskalenko's claims but said they were reluctant to comment on the seriousness of the case before the results of further forensic testing were known.

An assistant prosecutor, Claude Palpacuer, said an initial test indicated the substance found in the car was mercury but that the material had been sent to another laboratory for more sophisticated examination. The results of these were expected within days.

"No offense has yet been proven. At this stage we are staying very cautious about whether this is a criminal matter or whether it has come from her concerns, which are understandable, about the circumstances of her activities," he told the newspaper Libération.

Moskalenko and her family spent Tuesday undergoing tests at the Medical Legal Institute in Strasbourg. Officials at the center declined to give further details.

Yesterday's hearing was the first time that anyone has been brought to trial in connection with Politkovskaya's killing. It follows widespread criticism of the official investigation. Yesterday Moskalenko said that the case had not been properly investigated. "We were denied the basic right of getting access to the investigation. This violates the European convention on human rights," she said.

So far Russian prosecutors have failed to identify who ordered Politkovskaya's contract-style murder. They have also failed to catch the man they allege did it - a third Makhmudov brother called Rustam. He is said to have fled abroad.

Yesterday's preliminary hearing took place behind closed doors at Moscow's district military court. Colleagues from Politkovskaya's newspaper Novaya Gazeta said they would to have the trial held in open session when it resumes next month. Officials claim that secrecy is justified because much of the material involved is classified. A fourth man charged in the trial, Pavel Ryaguzov, is a Federal Security Service officer who is accused of criminal links with Khadzhikurbanov in an earlier case. He was one of the original suspects in the case but is no longer suspected of being linked to Politkovskaya's killing.

Politkovskaya, 48, won international acclaim for exposing the brutality of Russian forces and human rights abuses in Chechnya.