'This Week' Transcript: Former Arkansas Gov. Mike Huckabee

— -- Below is a rush transcript and may contain errors. It will be updated.

ANNOUNCER: A special edition of This Week: Terror Flash Point. 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 Flash Point.

Here now chief global affairs correspondent Martha Raddatz.

MARTHA RADDATZ, ABC NEWS CORRESPONDENT: Good morning. So many developing stories this weekend. Just two days from the president's State of the Union.

And 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. But, first, the fast moving developments in that 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 all the breaking developments from Brussels. Good morning, Alex.

ALEX MARQUARDT, ABC NEWS CORRESPONDENT: 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.

(BEGIN VIDEOTAPE)

MARQUARDT: Across Europe this morning, countries at their highest alert. 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 scene, indicating an attack very likely. And here in Belgium, heavily armed troops patrolling the streets for the first time in 30 years.

You can see here these Belgian soldiers armed with machine guns standing outside the American embassy, one of many sites officials fear could be a target.

As security is beefed up, the authorities are also 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 went to Syria to fight with ISIS. Now, possibly in Greece.

Belgium is a tiny country with just over 11 million people. But some 300 to 400 young men have traveled to Syria to fight, the highest per capita of 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 the police. In their hideout, AK-47s, explosives and police uniforms.

It's not just police who are believed to be some of the main targets, but Europe's Jewish communities as well.

UNIDENTIFIED MALE: The threat is serious, because they are a target we know terrorists like. They need to be protected.

MARQUARDT: In Paris, where anti-Semitism is on the rise, we saw police evacuating a synagogue.

UNIDENTIFIED MALE: All the signs are there. See the police outside of the synagogue? Don't see them outside of a mosque. It's quite magic.

MARQUARDT: Is it getting worse?

UNIDENTIFIED MALE: I hope not.

(END VIDEOTAPE)