Hundreds of people who had been gathered at Place de la Republique in central Paris dispersed suddenly on Sunday evening in what police later said seemed to be a false alarm.
With Parisians' nerves still on edge after Fridays shootings and suicide bombings, people suddenly all began running away from the square, a Reuters witness at the scene said.
"There was crowd movement with apparently with no reason. We hadn't heard anything and all the people we questioned hadn't heard anything either," a police official at the square told Reuters.
TV pictures that had earlier been showing people gathered around a monument to commemorate those killed in Friday's Islamist militant shootings later showed the scene nearly empty.
An official from the emergency services said some members of the public had believed they had heard gunfire.
There was also panicked movement of crowds outside a bar that had been the scene of a shooting on Friday, and where people had gathered in vigil Sunday evening. A second police official said that had also been a false alarm.
