A neo-Nazi former soldier has reportedly turned himself in for questioning over the shootings that have shaken the French town of Toulouse.
According to reports the man, who has not been named, presented himself to police on Tuesday morning.
The man was one of three soldiers from France's 17th Parachute Engineers regiment who were photographed giving a Nazi salute in front of a swastika in 2008.
The soldiers were fired after the picture emerged.
Police were seeking the men in connection with the fatal shootings of three children and an adult outside a Jewish school on Monday.
Based on ballistic evidence from the guns used in the attack, police were also linking the men to the shootings of two soldiers from the disgraced soldiers' former regiment on 15 March and another soldier on 11 March.
The men were described by French media as "muscular and tattooed".
France's Le Point news magazine said: "This is the first real lead the police have. [It is believed] there could be a link to the three soldiers dismissed from the army four years ago.
"The profile of these men corresponds to the scant information investigators have on the Toulouse killer, that is to say, muscular and tattooed.
"This lead is being followed up by both civilian and military authorities."
All of the soldiers who were killedwere reported to have been black or of north African origin.
French president Nicolas Sarkozy said there were "similarities" between the shootings, but said the country must wait for police to carry out their investigations before the "hypothesis" could be confirmed.
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