Transcript for The Hunt for Paris Shooter's Partner
this evening, French authorities are now warning they are on the hunt for other members of that terror cell behind those Hor riff you can attacks in France. Including this woman. The most wanted woman in the world, believed to have slipped into Syria. Here at home tonight, a hack attack on a Twitter account run by the U.S. Military, the chilling message, "I love Isis" and the new threat. This evening, urgent new warnings. Homeland security being stepped up across the country. ABC's Brian Ross leading us off from New York. Brian? Reporter: Good evening, David. French officials confirm tonight, they are urgently searching for possible terrorists on the loose. People who they feel are well armed and dangerous. As French authorities tonight search for other members of the terror cell, new video emerged of two that got away. On the right, hayat boumedienne, the girlfriend of the gunman at the Paris grocery store, and on the left, another alleged accomplish, seen at this Turkish immigration checkpoint last week. French authorities say they left Paris just before the attack and moved first to Madrid, then istanbul before crossing the border into Syria, where today they were reported by Isis followers to have arrived in the terrorist stronghold city of raqqah. She is outside the reach of French law enforcement and it's going to be difficult to even conduct surveillance of her activities while she's in Syria. Reporter: As for her boyfriend, officials are analyzing this so-called martyrdom tape, recorded by am amendy Coulibaly, swearing allegiance to Isis and the surprising array of firepower he somehow accumulated. The two other Paris attackers, the kouachi brothers, also had their own deadly arsenal, as seen in these surveillance photos made public today show them holding up a gas station with a disposable rocket launcher over the shoulder of one of them. Powerful enough to stop an armored vehicle. An incredibly serious military weapon. But it was another Isis weapon today that got the attention of the U.S. Military. The terror group's followers using keystrokes instead of kalashnikovs to take over the Twitter feed and youtube channels of the U.S. Military's central command, headquarters for American efforts against the terrorists. The hackers posted Isis videos, and issued this threat -- "American soldiers, we are coming, watch your back." And Brian is back with us now. When we learned of this hack attack, so many wondering, was any classified information put at risk? Reporter: The military says no classified information was involved. But the apparent ability to deliver the threat has brought about a full investigation.
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