Authorities seek suspected militants as U.S. warns of attack threat

U.S. authorities have warned of potential militant attacks in Italy, whose security services are looking for five possible suspects, Italy's foreign minister said on Thursday.

Speaking to state broadcaster RAI, Paolo Gentiloni referred to "possible terrorist attacks" that could be aimed at St. Peter's Basilica in Rome or the cathedral or La Scala theatre in Milan.

The U.S. embassy in Rome said in a message to its citizens that - alongside the big tourist destinations - churches, synagogues, restaurants, theatres and hotels in the country's two main cities could also be targets.

There was no suggestion from authorities that the threat encompassed plans for a specific attack.

Italy raised its security alert level to 2, the highest possible in the absence of a direct attack, following events in Paris on Friday, when Islamic State gunmen and bombers killed 129 people.

"As of yesterday our security forces are working to identify five people," Gentiloni said, adding that the U.S. embassy's warning did not constitute a recommendation that its citizens should avoid to Italy.

The embassy urged Americans to be vigilant as militant groups "may possibly utilise similar methods used in the recent Paris attacks".

"No one is going to put boots on the ground in Syria, not (French President Francois) Hollande, nor Obama, nor us," Gentiloni said.

Like much of Europe, Italy is reluctant to join France and the United States in conducting air strikes over Syria because, without an express request from a government it recognises, it considers the legal justification uncertain.