A French prosecutor is reported to have opened an inquiry into working conditions at a Renault technical design centre after three workers there committed suicide since last October.

The latest incident involved a man who died at his home last week, leaving a letter blaming work difficulties for his death, a Reuters report said.

It added that, in January, another worker drowned himself in a lake near the centre while a third killed himself by jumping from the fifth floor of the main building of the centre last October.

“We have opened an inquiry into the working conditions of the people who committed suicide,” Michel Desplan, the public prosecutor in Versailles, told Reuters on Wednesday.

The CFDT union reportedly said that workers had been under increasing pressure since the company introduced a restructuring plan last year and called for Renault management to urgently evaluate the situation.

“Since 2006, with the Renault Contract 2009, we have seen a sharp increase in work, a race for deadlines and developing in an activity that is becoming more and more complex,” the CFDT said in a statement cited by the news agency.

A Renault spokeswoman told Reuters the company “deeply regrets” the incidents and extends its respect to the families, and said the company was looking into how “these unfortunate suicides” could have been prevented.