Policemen also found the body of a dead woman in the house and a surviving 3-year-old boy, the spokesman for the Interior Ministry, Pierre-Henry Brandet, said on BFM TV minutes after the elite RAID unit stormed the house.
The woman was "most probably the wife" of the commander, prosecutor Vincent Lesclous told reporters.
"We have no certainty about the motivations" of the assailant, Lesclous added. (Reporting by Mathieu Rosemain, editing by G Crosse)
Islamic State was responsible for the stabbing death of a police commander in front of his home in a Paris suburb Monday night, the militant group's Amaq news agency said.
"Source to Amaq agency: Islamic State fighter kills deputy chief of the police station in the city of Les Mureaux and his wife," Amaq said on its news website.