ST JOHN'S, ANTIGUA AND BARBUDA (AFP) - Massive power outages struck the Caribbean island of Saint Vincent before dawn on Sunday (April 11), as officials recorded more explosive activity at a long-dormant volcano that launched into a series of eruptions.

After remaining quiet for nearly 42 years, La Soufriere rumbled back into life on Friday, blanketing the island in ash and permeating the air with the stench of sulphur.

The eruptions prompted thousands to flee for safety, with around 16,000 people living in areas under evacuation orders.

The country's National Emergency Management Organisation (Nemo) noted "another explosive event" early on Sunday morning with the "majority of the country out of power and covered in ash".

The volcano's explosive phase is expected to last several days or even weeks, according to the Seismic Research Centre at the University of the West Indies (UWI), which advised residents to avoid inhaling the volcanic ash.

The whitish powder caked roads, homes and buildings in Saint Vincent after the powerful blasts began on Friday and continued into the night.

"Saturday morning on the island of over 110,000 residents looked like a winter wonderland, albeit blanketed by ash," news portal news784.com said.

Visibility in some areas was extremely limited.

While the volcano lies on the island's northern end, the ash caused a thin haze of dust in the capital Kingstown on the south end, the portal said.

The thick clouds of dust expelled by La Soufriere have affected neighbouring islands as well, travelling over 175km east to Barbados.

"Barbadians have been urged to stay indoors as thick plumes of volcanic ash move through the atmosphere," the Caribbean Disaster Emergency Management Agency said.

The initial blast from La Soufriere, the highest peak in Saint Vincent and the Grenadines, sent plumes of hot ash and smoke 6,000 metres into the air on Friday morning.

Smaller eruptions took place on Friday afternoon and Saturday, belching out further columns of ash, according to the UWI researchers.

Vincentian Prime Minister Ralph Gonsalves said on Saturday that water has been cut off in most areas and the country's air space is closed because of the ash.

Around 3,000 people spent the night in shelters.

"It's a huge operation that is facing us," Mr Gonsalves told NBC News.

He said his government has been in contact with other countries that want to provide aid and that Guyana and Venezuela are sending ships with supplies.

Evacuation orders

The 1,235m La Soufriere - French for "sulphur mine" - had not erupted since 1979, and its largest blow-up happened over a century ago in 1902, killing more than 1,000 people.

It had been rumbling for months before it finally blew.

"We are trying to be okay. It's deathly quiet outside and the mood is pensive," said Ms Vynette Frederick, 44, a lawyer in Kingstown.

North-west of Kingstown on the 30km-long island, Ms Zen Punnett said things had calmed down after the initial panic as evacuation orders came out on Thursday night.

"It's gotten hazier. We are staying inside," she said.

The emergency management agency posted photos of a Coast Guard ship evacuating residents of an area who had previously refused to leave.

Standing on a dock, the air above the evacuees was a chalky gray.

Most of the people in the red zone had been moved to safety by Friday, authorities said.

Cruise ships were on the way to assist the evacuation effort.

The Saint Vincent and Grenadines police on Saturday issued an appeal for troublemakers to stop making prank calls to emergency responders.

"We are in the middle of a serious evacuation and security exercise, to safeguard and rescue persons who are affected by the eruption," the agency said.

"These irresponsible calls divert much-needed resources and personnel from the evacuation exercise."