A man accused of beheading his boss at a gas plant has committed suicide in prison, French police confirmed to NBC News on Wednesday.
France's national police said Yassin Salhi, 35, had hanged himself in prison on Tuesday.
Salhi was facing terrorism charges following the grisly attack in June at an Air Products plant in Saint-Quentin Fallavier in southeastern France.
French authorities alleged that Salhi — a truck driver with a history of radical Islamist ties — took a "selfie" with his victim's decapitated head and sent the image to a friend in Syria.
Lawyer Samia Maktouf, who represents victims of the recent Paris attacks, said Salhi death rules as a suicide will leave victims of terrorism feeling cheated.
"His death is a complete non-respect to the victims," said Maktouf, who has represented 25 victims of terrorism in France over the last two years. "He killed himself deliberately to carry out a second terrorist attack on himself."
She added that Salhi's death shows that authorities still have a lot to learn.
"In the culture of ISIS, he becomes a martyr," Makhtouf said. "I am angry because he was allowed to do this. We still don't understand the death culture, which is at the heart of this fanaticism."