Passengers were ordered out of Nice Airport, according to the Associated Press. The terminal building was sealed off and military personnel were visible inside.
The alert at the airport was lifted shortly afterward and passengers were allowed back into the terminal to pick up their bags.
The airport's website showed flights leaving and landing as usual. In a message posted to the site's home page, the airport said: "Despite the dreadful events that occurred, access to the airport and Air traffic won't be disrupted."