Smelly foam closes famed Italian sea cave

NAPLES, Italy, Aug. 25 (UPI) -- A smelly foam caused officials to close the popular Grotta Azzurra sea cave on the Naples bay island of Capri Tuesday.

The fumes emitted by the white foam were so strong one of the workers who ferry people to the site had a dizzy spell, and some tourists said they felt ill, too, ANSA reported.

Police said the Capri grotto, once used by Roman Emperor Tiberius as his private swimming pool, would remain closed until biologists and health experts determine the nature of the substance, the Italian news agency said.

Last week, raw sewage was discovered nearby.

The waters inside Grotta Azzurra are known for the color produced by sunlight passing through an underwater cavity and shining through the seawater.