The attack in Cannes comes as worries over violent crime and terrorism feature among voters' main concerns, in the run-up to the 2022 French Presidential election.
"I am going to the scene immediately this morning and I offer my support to the national police and to the city of Cannes," added Darmanin on his Twitter account, Reuters reported.
BFM TV, citing a police source, said the attacker opened the door of a police car stationed in front of the police station, stabbing the policeman at the wheel with a knife.
He then tried to attack a second policeman in the car but a third policeman in the car fired his weapon, seriously injuring the attacker.