Police are hunting for convicted arsonist who escaped from London's Pentonville prison shortly after he was counted off the security van.

Frenchman Julien Chautard, 39, copied Robert De Niro's psychopath character Max Cady in the thriller "Cape Fear" by clinging to the underside of the van and staying there as it left the jail.

His escape on Friday went undetected for seven hours as prison officers searched the prison until 2 a.m.

“The van went into the prison’s secure area, then they unloaded the prisoners," a source told The Sun. “Normally as prisoners come off the vehicle and into the building there is somebody who searches and escorts them — but there wasn’t this time.“

"When the van was checked afterwards they found foot prints and finger hold marks on the underside.”

It was only when CCTV footage was checked hours later that officers noticed a shadow under the van that had not been there before.

Chautard had been sentenced earlier in the day at Snaresbrook Crown Court to seven years imprisonment for two counts of arson, Scotland Yard said.

Police said he has connections in France and also has links to the Hackney, Edgware and Kings Cross areas of north London.

"The circumstances around the escape will be fully investigated," the Ministry of Justice said.

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