Secret communications from both hostage scenes in Paris enabled armed officers to pinpoint the moment they could storm the locations.

French prosecutors told reporters there was evidence the gunmen in both incidents knew each other.  

An audio recording posted online yesterday purportedly by the leader of the Yemeni branch of al Qaeda said the attacks were prompted by insults to prophets, but didn't claim direct responsibility for the attacks.

At the Hyper kosher store in Porte de Vincennes, in the east of the capital, officers seized upon the moment terrorist Amedy Coulibaly knelt down for evening prayers to pile into the building and free the hostages.

There were 19 men, women and children inside the store when Coulibaly, 32, entered, and he killed four people immediately.

Police later stormed the building in a volley of rapid fire and smoke, killing the terrorist as he attempted to flee and freeing the 15 remaining hostages.

Officers had secretly listened in to the situation after the hostage-taker apparently failed to hang up properly when making demands by telephone.

Across the city, one man hid out of the view of killer brothers Said and Cherif Kouachi and relayed secret information to police before they stormed the print works in Dammartin-en-Goele as the three-day manhunt reached a dramatic conclusion.

Prosecutor Francois Molins told how the employee at the location was cowering on the second floor underneath a sink.

The brothers did not realise there was another person hiding in the warehouse.

The brothers were responsible for the Charlie Hebdo massacre in which 12 people - including journalists, cartoonists and police - were killed.