Twelve people were injured after a grenade was thrown into a lively bar in the French city of Grenoble, local authorities said.
The incident happened at the Aksehir bar shortly after 20:00 local time (19:00 GMT) on Wednesday night, leaving two people in critical condition.
The motive for the attack is not clear, but investigators say “can be associated with resulted in scores.”
Prosecutor Francois Touret-De-Courcey said eyewitness accounts suggest that the suspect, who has not yet been identified, may also have carried a Kalashnikov rifle.
Speaking to reporters at the scene, he said, “There is nothing to make us think that he is related to terrorism,” describing the incident as an “act of extreme violence.”
He added that investigators are considering drug trafficking.
Authorities said many people were in the place in the city district of the Olympic village when the suspect was briefly entered.
About 80 firefighters and police officers were located at the scene, with the area being fenced on Thursday morning, French paper Le Figaro reports.
Deputy Mayor Chloe Pantel told the AFP news agency that the place is “a place where locals and people outside the neighborhood are gathering, especially to watch football matches.”
The police presence in the area will remain for a while, she added.
By publishing the X, Mayor Eric Piol condemned what he described as a “criminal act of extreme violence” before thanking the rescue and security forces “for their rapid intervention.”