Starting right now, a special edition of "This week," terror flashpoint. All of Europe on edge. In London, police on their highest alert, ever. In Belgium, a plot foiled in its final hours. Soldiers... See More
Starting right now, a special edition of "This week," terror flashpoint. All of Europe on edge. In London, police on their highest alert, ever. In Belgium, a plot foiled in its final hours. Soldiers now deployed on the streets. It's a worldwide terror crackdown. This morning, we're answering the urgent questions. Can Europe prevent another attack? And are there sleeper cells here at home? From the global resources of ABC news, a special edition of "This week, terror flashpoint." Here now, chief global affairs correspondent Martha Raddatz. Good morning. So many developing stories this weekend. Just two days from the president's state of the union. Big news in the race to be the next president. Mitt Romney and Mike Huckabee, both on the verge of jumping in. Governor Huckabee is our exclusive guest this morning. First, the fast-moving developments in the global terror crackdown. This morning, more arrests in Europe. Police raids happening in four european countries so far. U.s. Investigators also joining in as the international manhunt for sleeper cells heats up. ABC's Alex Marquardt has the breaking developments from Brussels. Good morning, Alex. Reporter: Good morning, Martha. An intense feeling of nervousness. In Europe this morning. You can see here at the American embassy, the increased security measures that have been taken. A scene playing out across the continent as authorities try to prevent another attack. Across Europe, countries at their highest alerts. In France, following the Paris attacks, 120,000 soldiers and police in the streets. In the UK, the threat level against police raised to a level never before seen. Indicating an attack is very likely. And here in Belgium, heavily armed troops patrolling the streets for the first time in 30 years. You can see here the Belgian soldiers armed with machine guns standingout side the American embassy. One of many sites officials fear could be a target. As security is beefed up, the authorities are cracking down. In the past 72 hours, almost three dozen people across Europe have been arrested on suspicion of terror-related activity. Just last night, two detained in Athens, Greece. Belgian media reporting that authorities are hunting for a 27-year-old Belgian who is possibly in Greece. Who went to fight with Isis. Belgium is a country with 11 million people. Some 300 to 400 young men have traveled to Syria to fight, the highest per capita in any western country. Some of them arrested on Thursday in a series of Belgian raids. Just hours before authorities say a terror cell was going to launch attacks against police. In their hideout, ak-47s, explosives, and police uniforms. It's not just police that are believed to be some of the main targets. But Europe's jewish communities as well. They are a target. We know terrorists like. They need to be protected. Reporter: In Paris, where anti-semitism is on the rise, we saw police evacuating a synagogue. All the signs are there. You see the police outside the synagogue. Not outside the mosque. It's -- quite tragic. Reporter: Is it getting worse? I hope not. Reporter: Top european counterterrorism leaders say with all the europeans going to fight in Syria, there are thousands of potential terrorists that could carry out attacks, another of which they say is inevitable. Martha? Thanks, Alex. Let's get the latest on the sweeping terror raids across Europe. And new fears that sleeper cells are poised to strike again. Rob Wainwright is tracking all of it as director of the european union low enforcement agency, europol. Dozens of people arrested across Europe. What is the connection between them? What we're seeing now, Martha, is a determined police response. Right across Europe. To deal in the aftermath of the terrible attacks in Paris. We see action in Belgium. In Greece, in Berlin, other locations as well. It shows the nature of the threat that we're facing right now. It's spread across so many european countries. Perpetrated by a community of possibly thousands of people ho have been radicalized on the internet by their conflict experience in Syria and Iraq. Many of them have returned to european society. Perhaps some of them with the intent and capability to carry out the attack. And to your question, I'm not sure that there is such a network, an organized network of people who are operating under command and control structure. It's a lot more diffuse and unconnected in nature than that. Which can be more dangerous? A lot of independent or semiindependent people. Of course, that makes it much more dangerous. That's the challenge the police face. Not just the scale of the problem, the Numbers of people involved, the way in which -- it's much looser than we have seen before. It's not the same as in the days of 9/11, when we had an identifiable command and control structure. It's moving insidiously. Across the internet in particular. It's a challenge for police right now. You have said that Europe is facing its most severe threat since 9/11 and this might be worse. I think it's -- it is more difficult. More challenging than at any time since that period. Because of the complex way it operates in our society. But at the same time, we're seeing a very determined response by our national governments. By national police authorities. And that institutions like europol organizing to better support counterterrorist services everywhere and the exchange of intelligence. And the tracking of terrorist financing and elicit fire arms. Monitoring activities online. In all of these areas, it's important we scale up our resources so that together, we can protect our citizens in a better and stronger way in the future. We keep hearing this term, sleeper cells. Define that for us. Their secretive. How do you find them? Let's give you the example of what happened in Paris. Here, counterterrorist services were prioritizing their investigation around these people who had just returned from Syria and Iraq. Who had embedded them back into society. Perhaps some of them planning to carry out terrorist attacks. In the meantime, the people responsible for the outrages in Paris were part of what was thought to be a dormant cell, not active since 2005, 2006. So what it shows you is that even so called older cells, sleeping in nature, can wake up at any time and carry out terrible attacks. It's much more complex than we thought. It's important to increase the scale of the international collaboration with the U.S. Authorities. So we can get a better picture of the threat they pose to society at the moment. Thank you so much for joining us, Mr. Wainwright.
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