Arrests in France, Germany amid terror tension

French and German authorities arrested at least 12 people Friday suspected of links to the Islamic State in Iraq and the Levant (ISIL) and a Paris train station was evacuated, with Europe on alert for new potential terrorist attacks.

The police raids came the morning after Belgian authorities moved swiftly to pre-empt what they called a major impending attack, killing two suspects in a firefight and arresting a third in a vast anti-terrorism sweep that stretched into the night.

Visiting a scarred Paris on Friday, U.S. 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 satirical newspaper Charlie Hebdo and on police.

Hollande thanked Kerry for offering France support, saying, "You've been victims yourself of an exceptional terrorist attack on Sept. 11. You know what it means for a country. ... We must find together appropriate responses."

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 10 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 ISIL. 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 ISIL extremists in Syria and Iraq.

Two people were killed during a Belgian police operation Thursday targeting a group said to be planning "terrorist attacks on a grand scale," according to federal prosecutors.

Magistrate Eric Van der Sypt told reporters at a news conference in Brussels that police had stormed an apartment above a bakery in the town of Verviers shortly after dark. The suspects immediately opened fire, but were quickly "neutralized," he added.

The two killed were both Belgian citizens, as was another individual who was taken into custody. There were no casualties among the security forces involved in the operations. 

The raid, which had been in the works for weeks, did not appear to be linked to last week’s attacks in Paris. According to Van der Sypt, "The searches were carried out as part of an investigation into an operational cell some of whose members had returned from Syria."

Unlike the Paris terrorists who targeted the offices of the satirical weekly Charlie Hebro, the suspects in Belgium were reportedly aiming at hard targets: police installations.

"They were on the verge of committing important terror attacks," Van der Sypt told a news conference in Brussels.

The scene of the operation — a residential area in the town of about 50,000 people, close to the German border — was cordoned off with ambulances, police vehicles, and a bomb squad spotted at the site, according to witnesses who posted photos to Twitter. They also reported hearing several explosions and heavy gunfire.

The operation was part of a nationwide sweep against suspected extremist groups, including people believed to have returned to Belgium after taking part in the Syrian civil war. Van der Sypt confirmed that similar raids were ongoing in the Brussels region as well as Verviers.

In the wake of the Paris shooting attacks, which left 20 people dead, most of Europe has been on high alert.

According to local press, a Belgian arms dealer sold the weapons used by at least one of the Paris attackers, Coulibaly, who killed four people at a kosher grocery store in east Paris. His apparent accomplices, Said and Cherif Kouachi, had earlier gunned down 12 at the offices of the French satirical magazine Charlie Hebdo.

The Belgian dealer, Neetin Farasula, turned himself in to police on Tuesday.

Belgium is believed to have the highest percentage of citizens in European countries who have left to fight for insurgent groups in Syria, including Islamic State of Iraq and the Levant (ISIL), according to data compiled by security researchers.

A court in Antwerp was due this week to deliver a verdict on 46 people accused of recruiting young volunteers to fight in Syria, but it has been delayed for a month over the Paris violence.

Al Jazeera and wire services