Three intelligence sources told The Daily Beast that the ban on carry-on electronics aboard U.S.-bound flights from 10 airports in North Africa and the Middle East was the result of information seized during a U.S. raid on Al Qaeda in Yemen in January. The United Kingdom joined the U.S. ban Tuesday.

Information from the raid shows al Qaeda's successful development of compact, battery bombs that fit inside laptops or other devices believed to be strong enough to bring down an aircraft, the sources said. The battery bombs would need to be manually triggered, a source explained, which is why the electronics ban is only for the aircraft cabin not checked luggage.

The U.S. Department of Homeland Security publicly cited two attacks on flights in the last two years, the downing of a Russian jet over the Egyptian Sinai in October 2015 and an attempt that nearly succeeded in bringing down a jet that had taken off from Mogadishu, Somalia last year and made an emergency landing after an explosion ripped open its cabin. The insurgent group Al-Shababb claimed credit for getting a laptop onboard the flight that had been rigged as a bomb.

“Since they weren’t high enough, the explosion wasn’t catastrophic to the plane and they were able to land," one source told The Daily Beast. "The bomber got sucked out of the hole, but it was proof of concept."

DHS declined to comment on the intelligence, saying only "we employ a variety of measures, both seen and unseen, to protect air travelers."

A former British Army intelligence analyst told The Daily Beast that an investigation into the device suggested that it used a military grade high explosive that generates a supersonic shock wave. It was probably the same explosive used by "shoe bomber" Richard Reid: PETN, or pentaerythritol tritinate, which is hard to detect. It delivers high yield for its weight: just 100 grams can destroy a car.

Although the ban on laptops is based on the belief that the compact explosive inside a battery would have to be triggered by the bomber in the airplane the British analyst believes that a laptop might actually be equipped with a timer. “The timing mechanism can be quite small. In fact, it is believed that the Somali bomb was pre-timed. Therefore a ban that still allows laptops in the cargo hold does little to negate the threat.”

He also points out such a device could not be triggered remotely: “There is no phone reception at 30,000 feet and installing a link to a satellite connection would be too bulky.”

The chief bomb maker for Al Qaeda in the Arabian Peninsula, Ibrahim al-Asiri, has been working on packing even smaller devices, the source added. CNN first reported the news on Tuesday evening.

The problem with this theory is that it implies that the security screening of electronic devices at the 10 airports is no better than at the airport in a failed state like Somalia. The pilot of the Airbus A320 involved in that incident said of that airport: “the security is zero.” Airport employees had conspired with the bomber to get the laptop through security.

One source said the foreign countries included in the ban were selected because of their exposure to al Qaeda groups and members who might try to bring a battery bomb on a plane heading for the U.S.

Egyptian intelligence officials were briefed over the weekend, according to one source, and have long been concerned about another plane departing from Cairo being brought down like the Metrojet plane in Oct. 2015. And there is another disaster, EgyptAir Flight 804, from Paris Charles De Gaulle airport to Cairo in May that crashed into the eastern Mediterranean and killed 66 people.

The crash has subsequently been shrouded in mystery. In December the Egyptian authorities announced that a criminal investigation had been opened. They had had six months in which to analyze data from the airplane’s two flight recorders recovered from the wreck. But there was a dispute between the Egyptian and French about the cause. The French air crash investigators said that it was not possible at that stage to draw conclusions about the origin of the accident.

It is known from data transmitted from the Airbus A320 as it spiraled down from its cruise height of 37,000 feet that it suffered a rapid cascade of failures, beginning with an electrical problem in the cockpit. This escalated into a fire in the electronics bay below the cockpit that effectively fried the computers controlling the flight.

There were indications that the disastrous sequence started with some kind of explosion in the passenger toilet immediately above the electronics bay and behind the cockpit. Video taken of the wreck showed heat damage beneath the cockpit.

Before leaving Paris the airplane had flown from Asmara in Eritrea, to Cairo and then onward to Tunis and Paris. That means that investigators would be looking at the possibility of an explosive device being placed on the airplane at any of those airports.

In early March, a Russian passenger on a Turkish Airways flight from Alexandria to Istanbul was arrested after an improvised explosive was found in his luggage, according to a DHS alert in early March citing Egyptian media.

The gravity of the move had been underscored by the political response to it. Representative Adam Schiff, Californian Democrat and ranking member of the House Permanent Select Committee on Intelligence, said in a statement:

“Over the weekend I received an additional briefing by the Department of Homeland Security and I fully support the new security precautions. These steps are both necessary and proportional to the threat.”

Several Federal Air Marshals told The Daily Beast they were angry they were blindsided by the ban, only to learn about it from CNN or BBC news reports circulated by management. (President Donald Trump has repeatedly referred to CNN as "fake news.") But DHS spokesman said they shouldn't be surprised to not receive notification about something they aren't involved in.

"FAMS aren’t involved in this particular action so why would they be notified of an action that doesn’t directly affect their duties?" DHS spokesman David Lapan told The Daily Beast.

Federal Air Marshals only fly on U.S. carriers and the electronics ban involves direct flights into the U.S. from countries served by foreign airlines.

The most consequential impact of the new measures will be on the three airlines operating out of the Persian Gulf states: Emirates, Etihad and Qatar Airways. In the last decade there has been a major transformation of the connections between inter-continental airline routes. Led by Emirates from their hub in Dubai this has put the three airlines in a dominant position to connect flights from Asia, Africa, the Middle East and Europe and, significantly, to directly fly passengers from those regions to the United States.

Moreover, these airlines have set new standards of service, particularly for business class passengers. Anyone flying business class with these carriers finds the cabins glowing with the glare from many laptops as workaholic executives and managers use their flight time to catch up on work.

The three major U.S. international carriers, Delta, American and United, have found themselves left with fleets of older airplanes that can’t match the quality of cabin amenities of the Gulf airlines, who use latest generation jets like the Airbus A380 super jumbo and the Airbus A350. Over the last few years those airlines have pushed into major U.S. business centers like New York, Dallas, Houston, Chicago, Los Angeles, Boston and Seattle – scooping up, for example, major players in the energy and tech industries.

Craig Jenks, President of a New York base consultancy, Airline/Aircraft projects, pointed out that the ban’s effects reach far beyond the named airports.

In particular, Emirates, Etihad and Qatar Airways all have a high volume of passengers originating in Indian cities. Among these are many in high tech industries flying on from hubs in the Gulf directly to U.S. tech business centers like San Francisco, Seattle, Boston and New York.

“Now, all of a sudden, you arrive at a Gulf airport headed for San Francisco with your light carry-on and you discover, no laptop on board nor even while in transit at the hub. Intentionally or not, this is a negative for the Gulf carriers,” Jenks said.

Now that the ban has been joined by the UK, which has said that passengers on 14 airlines would not be able to carry laptops into the cabin of direct flights to London from Turkey, Lebanon, Jordan, Egypt, Tunisia and Saudi Arabia, the disruption to business travelers has become even more widespread.

Air travel remains a priority target for terrorists. And, once more, the mere threat of terror attacks has proved itself as costly, at least in economic impact, as the act of terror.

For example, one recent casualty has been Turkish Airlines. In 2015 it was following the Gulf airlines’ model to exploit the strategic location of Istanbul as a hub for the Middle East and Africa. In that year it made a profit of $872 million. Last year that became a loss of $463 million. Two events, a terror attack on Istanbul airport and the failed coup in July, as well as fear of new terror attacks, have put the airline into a financial crisis. Istanbul is on both the U.S. and U.K. list of airports covered by the new ban.