Does anyone remember anything quite like this happening before?

From the BBC:

Thousands of Roman Catholic pilgrims were evacuated from the Sanctuary of Lourdes in France after a bomb scare which turned out to be a hoax.

The threat came as 30,000 worshippers gathered for the annual Feast of the Assumption, one of the pilgrimage site’s busiest days of the year.

Police gave the all-clear for the site to reopen after a search by bomb disposal teams with sniffer dogs.

More than six million believers visit the Sanctuary each year.

It is famous for what many Roman Catholics believe was a vision of the Virgin Mary by a local girl in 1858.

It houses the shrine or grotto to Our Lady of Lourdes and on 15 August believers celebrate the Virgin Mary’s ascent to heaven.

A Church spokesman told French news agency AFP that a telephoned warning had been received by police, announcing that four bombs were going to go off at around 1500 (1300GMT).

He said the evacuation, just before the midday Mass, had taken place calmly.