Nicolas Sarkozy was taunted by fellow inmates who threatened to avenge the death of Muammar Gaddafi.
Mobile phone footage which appears to be taken by a prisoner at La Sante, a high-security jail in Paris, shows inmates shouting at the former French president.
On Tuesday (21 October), he began his five-year sentence for conspiring to finance his 2007 presidential campaign with funds from the Libyan dictator.
In 2011, Sarkozy’s France led Nato air strikes which helped rebels topple Gaddafi’s regime and resulted in the tyrant’s death.
One person can be heard shouting “Sarko, he’s right there, in an isolated area”, before adding that he is “going to have a bad time”.
“We know everything – we’re going to avenge Gaddafi,” they said. “Give back the billions of dollars.”