A suspected knifeman has killed two women at the main train station in the French Mediterranean city of Marseille on Sunday.
He was later shot dead by soldiers on patrol.
The suspect reportedly shouted “Allahu Akbar”, before slitting one of the victims’ throat.
French Interior Minister Gerard Collomb said about a dozen witnesses were being questioned.
“This act could be terrorist in nature but at this time we cannot confirm that,” he added.
“I was on the esplanade just in front of the station,” Melanie Petit, an 18-year-old student, told AFP.
“I heard someone shout ‘Allahu Akbar’ and I saw a man who seemed to be dressed all in black.”