A French doctor accused of intentionally poisoning 30 child and adult patients, 12 of whom died, was "above suspicion" at the start of a probe in 2017, an investigator said on Thursday.

Frederic Pechier, 53, worked as an anaesthetist at two clinics in the eastern French city of Besancon when patients went into cardiac arrest in suspicious circumstances between 2008 to 2017. Twelve could not be resuscitated.

He went on trial in the city Monday accused of triggering heart attacks in patients in an alleged attempt to show off his resuscitation skills and discredit co-workers.

Fabrice Charligny, a former police commander who was in charge of investigating the case, told the court Thursday that at the start of the investigation "Dr Pechier was above suspicion".

Pechier is suspected of tampe

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