A Defence Ministry official on the island, which has been home to a military base since Yemen's 1996 conflict with Eritrea, said its western part had "collapsed" into the sea.

Naval ships had been searching the surrounding waters for the soldiers. The island has no civilian inhabitants.

Canadian navy vessel Toronto, part of a NATO fleet sailing north towards the Suez Canal at the time of the eruption, was also conducting search and rescue operations at the request of the Yemeni coast guard.

"Toronto recovered one live survivor who was transferred to a Yemeni coastguard vessel, as well as two dead soldiers who were transferred to a Yemeni patrol boat," said Lieutenant Commander Angus Topshee, second-in-command on the HMCS Toronto.

Yemen's Oil Minister Khaled Mahfoudh Bahah said several earthquakes on Sunday had triggered the eruption.

Jamal al-Shalaan, head of the Yemeni Earthquake Centre, told state news agency Saba that three quakes with a magnitude of between 4 and 4.3 had struck the island at around 1127 GMT.

President Ali Abdullah Saleh had flown to nearby Hudaidah port late on Sunday and told the Yemeni navy to send rescue teams, Saba reported.

"A GIANT LIGHT SHOW"

Canadian Navy spokesman Ken Allan told Reuters from the HMCS Toronto that the volcano on the two-mile-long (3 km) island had spewed ash thousands of feet into the sky, but that activity had now died down.

"It was incredible. It was like a giant light show. As you got really close to it you could see the lava spewing down the east and west side ... right into the ocean," he said.

"It really lit up the sky. The smoke and the ash were rising thousands of feet up into the air. It was a three-quarter moon and it got blocked out many times."

Yemen's Maritime Affairs Authority issued an advisory for vessels to keep well clear of the island on the Bab al-Mandab passage at the southern entrance to the Red Sea, one of the world's shipping chokepoints.

But Yemen coastguard and shipping sources said that around 3 million barrels of oil per day which pass through the southern entrance to the Red Sea were unaffected by the eruption.

Oil tankers move through the passage en route to the Suez Canal or to the southern terminal of the Sumed pipeline in Egypt to supply crude to Mediterranean countries and beyond.