Anti-aircraft Hawk and Italian Spada missile units were deployed in the outskirts of the Italian capital as Rome's airspace closed down along with the city's second airport, where dignitaries are to land to attend Friday's funeral.

Italian Interior Minister Beppe Pisanu said the security operation "has no precedents in history."

NATO also joined the operation, deploying AWACS surviellance planes and F-16 jets that are to patrol the skies over the capital non-stop, being refueled in the air by a Boeing 707, Italian media reported.

If a small plane were to get past the tight security net, missile-armed helicopters would be ready to shoot it down, reports said.

Italy's aviation authorities said air traffic to Rome's main Fiumicino airport was being reduced by 30 percent due to the no-fly zone.

Road traffic throughout the city and its outskirts was also being barred from 2:00 am (0000 GMT) Friday until at least 6:00 pm in the evening, officials said, in a first in modern Roman history.

Up to 1,000 marksmen were to be deployed for the funeral in strategic points in Rome, many of them behind the statues that top Saint Peter's Square's colonnade, daily La Repubblica reported.

In all, more than 10,000 security forces will be involved in the operation to protect both the dignitaries and multitude that has reached Rome from all over the world over the past few days.

Police, soldiers and Italy's paramilitary Carabinieri worked overtime to control the crowds in the Vatican neighborhood, where tens of thousands continued to queue to see the body of the Polish-born pontiff lying in state at St. Peter's Basilica.

Units with explosive-sniffing dogs also patrolled the area, and Rome's Prefect Achille Serra appealed to pilgrims planning to attend the outdoor funeral at the square not to bring bags or backpacks to ease the work of security forces.

Serra insisted authorities had the "unprecedented" situation under control, adding that public offices would also be closed Friday along with schools.

He said the shutdown was ordered "to guarantee security and avoid a day of complete confusion."

"This does not mean Rome is in a state of emergency," Serra added.

Security measures faced their first test Wednesday evening with the arrival of US President George W. Bush, who immediately went to the Vatican to pay his last respects to the Polish-born pontiff.

Private planes were already barred from flying over the Italian capital as of Wednesday, as police helicopters hovered over the Vatican.

Italian President Carlo Azeglio Ciampi was briefed Thursday on the preparations for the funeral by Guido Bertolaso, the country's commissioner in charge of measures in Rome.

Ciampi was particularly worried that rain could further complicate preparations for Friday, but Bertolaso said rain was expected for later Thursday, not for Friday morning.

Asked whether he was worried about the security situation, Pisanu, Italy's interior minister, said: "I think the pope will continue to give us a helping hand."

John Paul II died Saturday following years of ill health.

All rights reserved. � 2005 Agence France-Presse. Sections of the information displayed on this page (dispatches, photographs, logos) are protected by intellectual property rights owned by Agence France-Presse. As a consequence, you may not copy, reproduce, modify, transmit, publish, display or in any way commercially exploit any of the content of this section without the prior written consent of Agence France-Presse.