A youth wielding a sabre took several young children hostage at a kindergarten in Besancon on Monday morning, television reports said, citing eyewitnesses.
A large police contingent was at the scene, with eyewitnesses saying a number of children had been freed, but that the man was still holding five children.
The reports said the man was armed with a sabre. There was no information about his motives.
The education minister, Mr Luc Chatel, was travelling to Besancon, some 250 km southeast of Paris, to be on hand in dealing with the situation. Further details were not immediately known.