Italy stepped up security at monuments, churches, trains and other sites across the country ahead of the Easter (search) holidays, an official said Thursday.

An interior ministry official stressed there were no specific threats, describing the move as a "routine measure."

The ministry official, who spoke on the condition of anonymity, refused to detail the security measures.

But Interior Minister Giuseppe Pisanu told parliament late Wednesday that security forces were now patrolling "moving targets," such as trains and subways, and that a network of cameras and explosive-detecting instruments had been put in place at some rail stations.

It was not clear if those security measures were put in place because of the holidays.

After the Sept. 11, 2001, attacks, security was tightened at museums, monuments and airports across Italy, as well as at the Vatican.

The Easter holidays draw millions of tourists to Italy.

In St. Peter's Square (search) at the Vatican (search), Easter celebrations started Thursday under tight security. The ANSA news agency said manholes were sealed along Via della Conciliazione, the large boulevard leading to St. Peter's, while Il Messaggero reported that the number of police was increased and that snipers were positioned on buildings overlooking the square.