The ex-head of France Telecom Didier Lombard has been placed under investigation for harassment over a slew of suicides during his tenure, as the probe widens to other former top executives.
Lombard, who ran the company between 2005 and 2010, was told on Wednesday he was being investigated for workplace harassment and put on bail of 100,000 euros ($A122,646), his lawyer Jean Veil said on Thursday.
Veil said Lombard had been heard by investigating magistrate Pascal Gand and "provided explanations on the economic, technological and regulatory conditions in which France Telecom evolved".
Lombard stepped down in March 2010 after 35 suicides among employees between 2008 and 2009.
Europe's biggest internet provider and its third mobile operator, trading internationally as Orange, France Telecom underwent major restructuring to confront growing competition.
During his time in charge, Lombard oversaw a huge reorganisation at France Telecom that involved the loss of 22,000 jobs between 2006 and 2008. In addition, more than 10,000 employees were switched to other jobs.
Veil said that Lombard had told the magistrate about "the particularly unfavourable competition rules that the government imposed on this business" when it was privatised.
Lombard wrote in Le Monde daily on Wednesday that the restructuring program, vital to remain competitive in a changing market was not responsible for the suicides.
"I am aware that the upheavals which rocked the company could have sparked jolts and problems," he wrote.
"But I firmly reject that these plans which were key to the survival of the company could have been the reason for these human dramas."
Although the suicide rate at France Telecom is lower than the French average, many of the employees had left notes blaming management decisions or stress at work.
Other former senior executives, including the company's former head of human resources Olivier Barberot, and Louis-Pierre Wenes, formerly number two at France Telecom, are due before the magistrate on Thursday.
Representatives of the company itself will face the magistrate on Friday and may be told that the company has also been placed under investigation.
A statement from the SUD union, which in 2009 filed a complaint over the suicides, welcomed news about the Lombard probe.
"It is the first time in France that a former business leader ... has been placed under investigation for moral and institutional harassment," it said in a statement.
Sebastien Crozier of the CFE-CGC union also welcomed the development.
"It's important for all the staff and the families," he said.
The union's lawyer, Frederic Benoist, said the way the redundancies program had been rushed through had put undue pressure on staff.
A 2010 report by work inspectors highlighted what it said was management harassment of the white-collar staff in particular, many of whom had been sidelined, urged to accept a career change or to leave the company.
France Telecom's management methods had effectively undermined staff psychologically, "undermining their physical and mental health", the report said.
Work inspector Sylvie Cattala wrote in a letter to a branch of the SUD union that between 2005 and 2009 management had repeatedly been warned of the dangers.
The formal investigation into the deaths at France Telecom was opened in April 2010 - the month after Lombard stepped down.
In April, police entered France Telecom's Paris headquarters to seize documents as part of that investigation.
France Telecom is one of the biggest companies in France, employing 105,000 people in France and 171,000 worldwide.