ATHENS (REUTERS) - Greek police said on Thursday they had arrested 10 foreigners for supplying forged passports and registration documents to refugees and other migrants arriving in the country.

An operation was under way on the island of Lesbos and in the Attica region surrounding Athens to dismantle the suspected criminal network that provided the fake identity documents, the police said in a statement.

News of the arrests came as a debate about security rages in Europe following last week's attacks in Paris in which 129 people were killed.

European Union interior ministers are expected to agree on Friday to tighten checks at the external borders of the passport-free Schengen area, a draft document seen by Reuters shows.

"This criminal organisation has provided more than 100 Greek passports and identity cards so far, charging between 300 and 700 euros depending on the document," a police official told Reuters, speaking on condition of anonymity.

He said Pakistani and Afghani nationals were among those arrested.

The fake registration papers had a forged Lesbos police stamp that meant the holders did not need to have their fingerprints taken by authorities on the island, he added.

The falsified documents were mostly used to allow the migrants to travel from Greece by plane. The fingerprints of those arrested would be sent to Interpol for checks, he said.

Greece, a member of the Schengen zone, is a major port of entry for refugees and other migrants fleeing conflicts and poverty in the Middle East and beyond.

About 600,000 migrants have so far arrived in Greece this year.

Most do not stay but head on to richer western European nations, especially Germany.