Anti-aircraft rocket launchers are in place around Rome, and a navy warship armed with torpedoes is patrolling the coastline near the capital. Those and other security measures are Italy's menacing message to terrorists ahead of Pope John Paul II's (search) funeral.
Although Italian authorities are playing down the threat of an attack, they're also taking no chances: Friday's funeral will draw millions of pilgrims along with U.S. President George W. Bush, two of his predecessors and dozens of monarchs, presidents and prime ministers.
There are plenty of reasons why militants might consider a strike, foremost among them Italy's involvement in the U.S.-led coalition in Iraq and an ongoing investigation into alleged Al Qaeda (search) cells in the northern city of Milan.
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And there are plenty of potential targets: Bush, who was flying to Rome on Wednesday; former U.S. Presidents George H.W. Bush and Bill Clinton; U.S. Secretary of State Condoleezza Rice; Britain's Prince Charles and Prime Minister Tony Blair; U.N. Secretary-General Kofi Annan; and a host of other world leaders and VIPs, including the presidents of Iran and Syria.
Perhaps most vulnerable are the huge crowds of pilgrims packing Rome for the funeral at St. Peter's Basilica (search). Officials say the capital of 3.7 million people could double in population by Friday. Two million Poles are expected as part of an unprecedented wave of other pilgrims.
"There are no signs to make us worry" about an attack, said Achille Serra, who heads the Rome prefect's office, one of several agencies responsible for security ahead of the pope's funeral.
But he added: "It's obvious that we would be naive to underestimate such a large-scale event and the possibility of a crazy guy causing problems."
One of Serra's deputies, speaking on condition of anonymity, told The Associated Press that "the current international situation and the number of people in the piazza call for measures of great attention." Authorities have no indications of a terrorist plot in the making, the official said.
Col. Massimo Fogari, a spokesman for the Defense Ministry, said anti-aircraft missiles were already in place around the capital. He would not say how many or confirm Italian media reports that rockets had been positioned on the ancient hills overlooking Vatican City.
A navy torpedo boat has been sailing up and down the coast near Rome, Fogari said. Italy's air force will be ready to scramble fighter jets during the funeral, and snipers will take up positions on rooftops, officials said.
Additional measures include intensified armed patrols on the Tiber River that flows through Rome. Air space within an 5-mile radius will be closed during the funeral, and traffic at Leonardo Da Vinci Airport will be reduced. Ciampino Airport, used for both civilian and military flights, will be shut down along with a smaller airport used by private and sightseeing planes.
Italy's elite Carabinieri military police increased their presence across the capital, part of an effort to bolster Rome's 10,000 police ranks by 6,500 and step up patrols with bomb-sniffing dogs. On Wednesday, a police helicopter made repeated low, sweeping passes over the city.
But the mood remained light even among the Carabineri, so famously laid back that their best-looking men and women officers are featured in a hot-selling calendar.
Only two uniformed officers were visible on the Piazza della Rotonda in front of the Pantheon, which was teeming with tourists Wednesday afternoon: one puffing on a pipe near the fountain, the other flirting with an attractive young sales clerk lounging in a doorway.
With the funeral fast approaching, Rome Mayor Walter Veltroni ordered a block on traffic in the city center starting eight hours before the service and running until Friday evening.
On Wednesday, Interior Minister Giuseppe Pisanu met with Italian police commanders and the chief of the domestic intelligence service on a plan "to guarantee the best conditions of security" for the funeral, the ministry said in a statement.
Underscoring the unique challenge of trying to secure the Eternal City, police have been crawling through Rome's warren of ancient drains and aqueducts under the city looking for bombs.
Italy has experience in dealing with the terrorist threat: In the 1970s and 1980s, homegrown militants from both the extreme right and left bloodied the nation with a series of attacks.
Pilgrims who lined up to view the pope's body at St. Peter's Basilica — neither screened at the entry to the square nor put through metal detectors before going into the basilica — seemed unconcerned.
"It didn't even cross my mind," said Therese Arbery, a 20-year-old college student from Dallas.