NEW YORK (CBSNewYork/AP) — Secretary of State John Kerry said “everybody is concerned” about more terror attacks in Europe in the future.

In an interview with CBS’ “Face the Nation” that will air Sunday, Kerry feared Europe will be threatened by more deadly attacks.

“Well, I think everybody is concerned, because for several years now, foreign fighters have been returning from Syria or from other locations and implanting themselves in communities,” Kerry said. “And this is the threat that we’ve all been aware of.”

The Islamic State of Iraq and Syria claimed responsibility for the terror attacks in Brussels that left more than 30 dead and hundreds of others injured.

Kerry told “Face the Nation” the United States is actively involved in helping to secure European cities.

“This is why we’ve been pushing for a passenger name recognition, flight manifest shared program within Europe that I hope will pass soon. We’ve been looking for additional screening,” Kerry said.

“We’ve been engaged actually with the Belgian authorities for some period of time now trying to fill gaps that they’re aware exist. And I think everybody is now geared up to recognize that the fight is not just in Iraq and Syria, but the fight is wherever those fighters have come from.”

Kerry also defended President Barack Obama staying in Cuba and attending a baseball game between the Cuban National Team and the Tampa Bay Rays the day of the Brussels terror attacks.

“The president of the United States’ schedule is not set by terrorists,” Kerry told CBS News. “Life doesn’t stop because one terrible incident takes place in one place.”

On the third and final day of national mourning, Kerry laid a wreath at the airport for the victims of Tuesday’s bombings — a ceremony that was skipped by Belgian Prime Minister Charles Michel because of the police operations.

Kerry, in a hastily arranged visit, defended Belgium’s counterterrorism efforts despite a series of security and intelligence failures before the bombings that have brought sharp criticism of top members of Belgium’s embattled government. Authorities believe both the Brussels attacks and the Nov. 13 bombings in Paris that killed 130 people were plotted from Belgium.

Kerry’s comments come as Belgian prosecutors issued an arrest warrant for a new suspect in the attacks on the Brussels airport and subway.

The federal prosecutor’s office said a warrant has been issued for a man only identified as Faycal C. He is wanted for “involvement in a terrorist group, terrorist killings and attempted terrorist killings,” the statement said.

A police raid was conducted at his home. No arms or explosives were found, prosecutors said.

Belgian media are reporting that a man called Faycal Cheffou has been identified as the man suspected of fleeing Brussels airport after two alleged accomplices blew themselves up there.

The developments come as Brussels airport officials moved to assess the damage caused by twin explosions at the terminal on Tuesday.

Authorities have wrapped up their investigation of the crime scene at the airport, and will allow engineers into the building to check its structural safety and information technology systems — and whether any damage can be repaired quickly.

Brussels Airport, which handles 23.5 million passengers annually, said it would be Tuesday at the earliest before flights resume.

The transport disruptions will do little to ease the worries of jittery Europeans, who are wondering how many violent extremists remain at large, and where and when they might strike again.

Heavily armed police swept into Brussels neighborhoods Friday in operations linked to the attacks. Signs of a large police operation remained visible Saturday at the quiet tram station in Schaerbeek district in Brussels where a man was shot.

The man, who was sitting with a young girl and holding a bag, was ordered by police “to put the bag far from him.” After he did so, police shot him twice.

Local residents have mixed feelings about the intervention.

“The security services are doing their work,” said Timotheee Bunkyezi, a 54-year-old student who believes that for such a large-scale operation, the intelligence the police were working on must have been solid.

But Marie-Madeleine Yamotia, a 40-year-old nurse who lives right opposite the bus stop, expressed concern for the child who was with the suspect.

“It’s traumatizing for the little one,” she said. “We don’t know. Is he really a suspect? Here, we doubt it a little.”

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