Police in central France have shot dead a man who attacked them with a knife while shouting "God is great!" in Arabic, French media report.
The man injured three police officers at Joue-les-Tours police station near the city of Tours before he was shot.
The assailant was a Burundi-born French national with a criminal record, a source close to the investigation told France's AFP news agency.
Anti-terrorism investigators were sent to the scene, the source added.
Christophe Crepin, a member of France's police union, told France 2 TV channel the attacker had had "a long knife, like a kitchen knife".
"He was banging on the fittings [of the door], so the officers opened [the door] to see what he was doing, and he immediately threw himself at my colleagues, stabbing one in the hand, and attacking the second on the neck and face," Mr Crepin added.
Investigators are reportedly focusing on whether radical Islam played a role and have launched an inquiry into "attempted murder and criminal conspiracy in connection with a terrorism organisation", the BBC's Lucy Williamson in Paris reports.
Some reports suggest the attacker's brother was known to have expressed a desire to travel to Syria, our correspondent says.
In 2012, French Islamist Mohammed Merah killed seven people in the city of Toulouse. He was eventually killed after a 32-hour siege at his flat in the city.