A former anaesthetist has gone on trial in the city of Besançon, in eastern France, accused of intentionally poisoning 30 people, including 12 patients who died.

Frédéric Péchier, 53, considered by colleagues to be a highly-talented practitioner, was first placed under investigation eight years ago, when he was suspected of poisoning patients at two clinics in the city between 2008 and 2017.

Despite the serious charges against him, Mr. Péchier has remained at liberty under judicial supervision and told French radio on Monday there was "no proof of any poisoning".

The trial is set to last more than three months and involves more than 150 civil parties representing the 30 alleged victims.

Allegations of poisoning emerged in January 2017, when a 36-year-old patient called Sandra Simard, who was otherwise healthy, had surgery on her spine and her heart stopped beating.

After an intensive care physician failed to revive her, Frédéric Péchier gave her an injection and the patient went into a coma and survived. Intravenous drugs used to treat her then showed concentrations of potassium 100 times the expected dose and the alarm was sounded with local prosecutors.

Another "serious adverse event", involving a 70-year-old man, happened within days, when Mr. Péchier claimed to have found three bags of paracetamol that had been tampered with after he had given a general anaesthetic.

Mr. Péchier said at the time he was being framed but a few weeks later he was placed under formal investigation.

One of Mr. Péchier's lawyers said he had been waiting eight years to finally prove his innocence, and the former anaesthetist told RTL radio on Monday that it was a chance to lay out "all the cards on the table".

"After I left, they still had [serious adverse events] and cardiac arrests. When I left in March 2017 they had another nine others declared afterwards," he told RTL radio.

Investigators then looked at other serious adverse events dating back to 2008, involving patients aged four to 89, at the two big healthcare centres he had worked at in Besançon - the Franche-Comté Polyclinic and the Saint-Vincent Clinic.

In 2009, three patients with no history of heart disease had to be resuscitated at the Franche-Comté Polyclinic during minor operations.

Twelve suspicious cases were found involving patients who could not be resuscitated, including several that could not be explained.

Damien Iehlen was the first fatality, in October 2008. Aged 53 he went into the Saint-Vincent Clinic for a routine kidney operation and died after a cardiac arrest. Tests later revealed he had been given a potentially-lethal dose of the drug lidocaine.

"It's appalling. You cannot imagine the effect it's had on my family," his daughter Amandine told French media. "It's unthinkable this could happen and that so many people were affected for so many years, from 2008 to 2017."

Frédéric Péchier comes from a family of health professionals; his father was also an anaesthetist.

Prosecutors argue that he tampered with intravenous medicines to induce cardiac arrests, as a means of getting revenge against colleagues. They say he was the "common denominator" in all the poisoning cases.

The trial is set to continue until December and the defendant will remain at liberty, under judicial supervision. If found guilty he would face life imprisonment. (BBC, but headline rejigged)

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