(Add Air France says threat is false alert)
PARIS, Dec 8 (Reuters) - Air France said an anonymous threat which led it to divert to Montreal its flight AF083 between San Francisco and Paris on Tuesday was a false alert.
"After a full security search, false alert confirmed by local authorities following an anonymous threat," the carrier said in its Twitter account.
The plane had taken off for Paris again.
Security officials worldwide have been on high alert since Islamic State militants claimed responsibility for attacks in Paris last month that killed 130 people. (Reporting by Marine Pennetier and Alan Charlish, writing by Maya Nikolaeva; Editing by Andrew Callus)
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