A vast “raft” of volcanic rocks covering 10,000 sq miles (26,000 sq km) of ocean has been spotted by a New Zealand military aircraft.
A naval ship was forced to change course in order to avoid the cluster of buoyant rocks, located 1,000 miles off the New Zealand coast.
The unusual phenomenon was probably the result of pumice being released from an underwater volcano, experts said.
One navy officer described it as the “weirdest thing” he had seen at sea.
Lieutenant Tim Oscar told the AFP news agency: “As far ahead as I could observe was a raft of pumice moving up and down with the swell.