A gunman took two women hostage in a jewellery store in the southern French city of Montpellier on Friday before giving himself up, officials said, adding the incident had no link to the Islamist violence around Paris.
After around seven hours of negotiations, the man surrendered to police, sources said.
"This man entered the jewellery store but there was no attempted robbery and his motive is not known," prosecutor Christophe Barret told reporters.
He had earlier told AFP that the incident was an armed robbery, insisting "it has nothing to do with what is happening in Paris".
The incident saw anti-terrorist police block off a large section of the centre of the Mediterranean city before the man gave himself up in the early hours of Saturday.
The two hostages were unharmed.