A day after a teacher was fatally stabbed in an Islamist attack, French President Emmanuel Macron ordered up to 7,000 soldiers to be mobilized for additional security patrols, his office announced on Saturday.

After a 20-year-old man fatally stabbed a teacher and critically injured two other people at a school in the northern French city of Arras on Friday, France was placed on its highest level of security alert.

Macron’s office said the soldiers would be mobilised by Monday evening until further notice as part of an ongoing operation that regularly conducts patrols in major city centres and tourist sites.

The Louvre museum, a major tourist draw in the French capital, was evacuated and closed after receiving a bomb alert, Interior Ministry spokeswoman Camille Chaize said, adding that checks were being made to establish there was no danger.

The latest security alert comes as France hosts the Rugby World Cup and less than a year before Paris welcomes the Olympic Games, which include plans for an unprecedented opening ceremony outside a stadium and a parade down the river Seine.

Chaize said security measures were already at their highest level at the stadium used for the rugby matches but extra patrols would be added at a fanzone nearby and in central Paris.

France has been targeted by a series of Islamist attacks over the years, the worst being a simultaneous assault by gunmen and suicide bombers on entertainment venues and cafes in Paris in November 2015.

The Interior Ministry said the security situation would be reviewed at a meeting on Saturday afternoon to decide whether additional measures are necessary, Chaize said.

Interior Minister Gerald Darmanin said on Friday the Arras attack bore a link to events in the Middle East, where Israel is conducting a military offensive to root out Hamas fighters after their deadly rampage into Israel last Saturday.