Arsonists set fire Thursday to a Jewish school north of Paris that had been badly damaged in another arson attack in 2003, police said. No one was injured. Officers detected the smell of fire on an overnight patrol near the Merkaz Hatorah school in suburban Gagny, then discovered flames jumping from a ground-floor room. Two school offices were destroyed. Police believe the arsonist threw an explosive device through a window. Two other small fires were set nearby as well. One targeted an abandoned car and another was set in a a garbage storage room. Firefighters contained the fires in less than a half hour. Police opened an investigation. CRIF, an umbrella group of France's Jewish organizations, asked investigators to shed all possible light on the case. A November 2003 fire at Merkaz Hatorah destroyed around 3,000 square meters (32,300 square feet) of the school. At the time, Interior Minister Nicolas Sarkozy said the arson attack had "an anti-Semitic and obviously racist connotation." The attack galvanized French leaders' response to anti-Semitic attacks. Days afterward, President Jacques Chirac announced a tougher policy to combat anti-Semitism, saying that an attack on a Jew is an attack on the entire nation. France has Europe's largest Jewish community - and, with an estimated 5 million Muslims, Europe's largest Muslim community, too. Anti-Semitic acts increased in France starting in 2000, reflecting the rise in Israeli-Palestinian violence. In recent years the number has been decreasing.