Dutch police have arrested 12 Somali men in the key port city of Rotterdam on suspicion of preparing a terrorist attack, public prosecutors said.
The men, aged 19 to 48, were detained on Friday on a tip from the intelligence services that they were planning an attack in the Netherlands.
There was no immediate information on the alleged target, but Rotterdam is Europe’s biggest port and a hub of maritime commerce, with huge oil and gas storage facilities and dozens of massive docks.
European officials stepped up security around the holidays this year after a Nigerian man last year left Amsterdam airport on Christmas Day and allegedly tried to blow up a plane over Detroit, Michigan, with explosives taped to his underwear.
There have also been growing holiday security concerns in Europe following a suicide bombing in Sweden and attacks on two embassies this week in Rome.
Dutch police searched an Internet cafe, four houses and two motel rooms in the Rotterdam area, prosecutors said on Saturday. No weapons or explosives were found. Six of the suspects lived in Rotterdam, five had no permanent residence and one came from Denmark, they said.
Asked how serious the threat was, a senior prosecutor said the intelligence tip warranted action.
“It’s uncertain whether we escaped from an attack. What we did is take away the threat that was formed by these people,” Gerrit van der Burg said on national NOS television.
Prosecutors must bring the suspects before a judge by tomorrow or release them.
The Dutch National Terrorism Coordinator left the terrorist alert level unchanged following the arrests, indicating the likelihood of an attack was “limited.”