France has been rocked by reports of a fresh hostage situation after the hunt for the Charlie Hebdo gunmen developed into a siege.

Said and Cherif Kouachi are holed up in an industrial estate with a hostage in a town around 25 miles from Paris following a car chase during which heavy gunfire was reported.

Meanwhile, multiple reports have emerged of a shoot-out in Porte de Vincennes in eastern Paris.

A hostage is said to have been taken at a kosher supermarket and the area has been evacuated by armed police.

It also emerged today that authorities believe there is a link between the brothers and the suspected perpetrator of a shooting yesterday in the Parisian suburb of Montrouge in which a female police officer was killed.

One person was reportedly hurt in the latest incident, while there were suggestions that there may be as many as five hostages.

The supermarket in question was named in reports as the Hypercasher Vincennes.

A Twitter user called David who said he was in a restaurant near the scene at Porte de Vincennes reported hearing gunshots.

He wrote: "Everyone is under the tables. The atmosphere is changing between nervous laughter and the first signs of stress."

He posted images of armed officers crouched at the side of a car, with the message: "Facing hypercasher."