More than two dozen suspects have been arrested in Belgium, France and Germany in continuing searches for suspected terrorists, authorities said on Friday.
Police forensic experts inspect the scene in Verviers, Belgium late Thursday after an anti-terrorist operation tha left two people dead. (EPA Photo)
Thirteen people were detained in Belgium and two arrested in France in an anti-terror sweep following a firefight in which two suspected terrorists were killed, and more suspects are being sought, Belgian authorities said.
French and German authorities on Friday arrested at least 14 other people suspected of links to the Islamic State group, and a Paris train station was evacuated, with Europe on alert for new potential terrorist attacks.
The developments came as the head of the European Union police agency warned that the large number of radicalised Muslim extremists across Europe, their lack of command structure and growing sophistication made it "extremely difficult" for law enforcement agencies to foil every terror attack.
Europol chief Rob Wainwright said in an interview that Europe needed to cooperate more closely to prevent attacks such as last week's deadly rampage in Paris.
"The scale of the problem, the diffuse nature of the network, the scale of the people involved makes this extremely difficult for even very well-functioning counterterrorist agencies such as we have in France to stop every attack," he said.
He believes that at least 2,500 and possibly up to 5,000 suspects have travelled from Europe to conflicts in Syria and Iraq.
On Thursday, Belgian police moved in on a suspected terrorist hideout in the eastern city of Verviers, killing two suspects and wounding and arresting a third.
Eric Van der Sypt, a Belgian federal magistrate, said the terrorists were within hours of carrying out a plan to kill police on the street or in their offices.
More than a dozen searches had led to the discovery of four military-style weapons including Kalashnikov assault rifles, Van der Sypt told a news conference.
"I cannot confirm that we arrested everyone in this group," he addeid.
US Secretary of State John Kerry lays a wreath to pay tribute to the victims of the attack on Charlie Hebdo, on Friday outside the weekly newspaper's offices in Paris. (AFP Photo)
Visiting a scarred Paris on Friday, US Secretary of State John Kerry met French President Francois Hollande and visited the sites of the city's worst terrorist bloodshed in decades.
Twenty people, including the three gunmen, were killed last week in attacks on a kosher supermarket and the offices of the satirical newspaper Charlie Hebdo and on police.
Paris is at its highest terrorism alert level, and police evacuated the Gare de l'Est train station Friday after a bomb threat. The station, one of several main stations in Paris, serves cities in eastern Paris and countries to the east.
The Paris prosecutor's office, meanwhile, said at least 12 people were arrested in anti-terrorism raids in the region, targeting people linked to one of the French gunmen, Amedy Coulibaly, who claimed ties to the Islamic State group. Police officials earlier told The Associated Press that they were seeking up to eight to 10 potential accomplices.
In Berlin, police arrested two men Friday morning on suspicion of recruiting fighters for the Islamic State group in Syria.
Across Europe, anxiety has grown as the hunt continues for potential accomplices of the three Paris terrorists, and as authorities try to prevent attacks by the thousands of European extremists who have joined Islamic State extremists in Syria and Iraq.
Hollande said France was "waging war" against terrorism and would not back down from international military operations against Islamic extremists despite recent deadly attacks.
"It is not a war against religion, it's a war against hate," he said in a speech to diplomats.