Transcript for Electronics restricted on flights from certain Middle Eastern airports

First to that breaking news about the ban on devices on board flights heading to the U.S. From eight countries. ABC's David Kerley starts us off from dulles airport with all those details. Good morning, David. Reporter: Good morning, robin. Hours ago this ban went into effect. Specific airlines and airports told electronic devices bigger than a phone like this not allowed on direct flights to the U.S. They're taking the step of banning electronics bigger than cell phones from the cabins of jetliners flying in from eight Middle Eastern countries. Including several ally, Egypt, Saudi Arabia, the gulf coast, all in an attempt to prevent this, a laptop stuffed with explosives smuggled on to a somali jetliner detonating after takeoff. It prevents laptops, tablet, camera and DVD players, it does not include phones or medical devices. They're trying to take an extra step that could take anything packed with explosives out of the cabin and prevent some sort of device being manually detonated. Reporter: The news first revealed by royal juror Dane an airlines apologizing saying they'll be strictly prohib at the timed. Other, ooipair, ethiad and emirates. The U.S. Government has some developed intelligence that a group as developed some type of device they can get on an airplane using a laptop or some other electronic appliance. Reporter: Now Saudi Arabia, another ally, its airline has told its passengers they will have to check their larger devices. The U.S. Has told these airlines and airports they have four days to comply with this order. Four days, David. For more let's bring in our global affairs correspondent Martha Raddatz and first of all, I want to ask about the reports that homeland security John Kelly phoned lawmakers over the weekend to brief them on some of the issues that led to this ban. Is that correct. Reporter: He did, robin. John Kelly did call some lawmakers to tell them about the new security threat. While it is not a specific threat, something triggered this urgent change and officials believe that some terrorist group is now capable of getting past airport security and carrying on a device that the current screening may not catch. This is also happening as many top Arab officials are headed to Washington to attend a meeting of the u.s.-led coalition against ISIS. Even though we do not know whether it is ISIS that is of the greatest concern with these new rules. There's also the possibility that the recent raid in Yemen where a Navy S.E.A.L. Was killed yielded some valuable intelligence, that's the home of an Al Qaeda bomb maker the U.S. Has long been after. We know you're familiar with these particular airports and people want to know why they were singled out and could others follow suit. These will for the most part major airports, especially dubai, one of the world's busiest airports, there's already strict screening there. One of the most thorough I have ever seen. They not only check you when you enter the gate but every passenger has an additional check of carry-on item by item but clearly the U.S. No longer thinks that is enough and maybe more will follow. That is clear. All right, Martha, thank you.

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