Updated

Spain and Morocco arrested 14 people suspected of forming part of a network to recruit and send fighters to Islamic State in Syria and Iraq, Spain’s Interior Ministry said Tuesday.

The operation, carried out Tuesday morning, comes as Europe remains on high alert after passengers on a Paris-bound train tackled and disarmed a man with guns and a box cutter on Friday, halting what authorities say could have been a deadly terrorist attack.

The attacker, Ayoub El-Khazzani, a 26-year-old Moroccan, had lived in Spain for seven years until 2014, and Spanish authorities had identified him as a potential security risk.

Spain's Interior Ministry said that Spanish and Moroccan police arrested the 14 people in San Martin de la Vega, about 18 miles south of Madrid, and several cities in Morocco, including Fez and Casablanca.

"The detainees formed part of a network to recruit and send foreign fighters to join the ranks of the terrorist organization Daesh (Islamic State), in the Syrian-Iraqi region under its control," Spain's Interior Ministry said in a statement.

Spanish authorities have been cracking down hard on suspected Islamic extremists since the January attack on the offices of Charlie Hebdo magazine in Paris, including working to stop citizens from fighting and training in the Middle East.

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