After hours of holding them under siege, the two brothers suspected of slaughtering 12 people at the Charlie Hebdo magazine were killed Friday when elite police stormed the building they were holed up in and freed a hostage unhurt. Sources close to the investigation said the explosions rang out when heavily-armed commandos made their move on a small printing firm in Dammartin-en-Goele northeast of Paris, killing the two massacre suspects. One police officer was injured.French police have exchanged fire Friday with the suspects. Al Arabiya channel stated that five military helicopters were hovering over the place involved in the chase. The channel reported also that the suspects held a hostage, before seeking refuge in a commercial building at the town of Dammartin-en-Goele, but the police succeeded in releasing the hostage. Police have identified the two suspects as Sherif and Said Kouachi, who were accused of carrying out France's bloodiest massacre in half a century at Charlie Hebdo. Meanwhile, A third gunman has taken hostages at a Jewish supermarket in Paris demanding the two be allowed to go free. "At the time of speaking, police forces are in the process, I hope, of apprehending the perpetrators of this act of savagery and making sure they can do no more harm," Prime Minister Manuel Valls said. No further details of the security forces' late afternoon operation were immediately available.