Police block the street at the scene of a shooting accident in Toulouse, France, on March 19, 2012. Three children and an adult were killed in a shooting outside a Jewish school in the southwestern French city of Toulouse on Monday morning, local media reported, raising the toll up from three.

A gunman killed four outside a Jewish school in the southwestern French city of Toulouse on Monday morning, prompting President Nicolas Sarkozy to put the region on its highest terror alert and drawing wide condemnation.

Calling the shooting a "national tragedy," Sarkozy, who rushed to the southwestern French city at noon, pledged to do everything to find the gunman.

"We have no choice but to face the challenges," he said.

The shooting took place outside the Ozar Hatorah Jewish school at around 8:00 a.m. local time (0700 GMT), just as students were arriving for school.

A professor, his two sons, and another 10-year-old student was killed before the killer fled on a motorbike.

Over 100 investigators were working on a manhunt for the gunman and had already identified the license plate of the motor bike used in the attack, media reported.

The attacker used a second gun when the first jammed, the Toulouse prosecutor said.

The incident follows the killing of three soldiers in two similar shootings last week in Toulouse on March 11 and in nearby Montauban on Thursday.

In a press statement released by the Elysee, Sarkozy confirmed that it was the same person with the same weapon "killed soldiers, children and the teacher."

The president announced a minute of silence in all schools throughout the country on Tuesday.

Sarkozy, who is running for a second term, announced to suspend his election campaign at least until Wednesday. Other main contenders including Socialist frontrunner in the presidential race, Francois Hollande, also said to cancel his campaign events after heading to the scene in the afternoon in Toulouse.