An explosive eruption has rocked La Soufriere volcano on the eastern Caribbean island of St Vincent following mandatory evacuation orders from the local government.
Erouscilla Joseph, director of the University of the West Indies Seismic Centre, said the ash column rose as high as 10 kilometres (six miles).
“There is heavy ashfall in the near vicinity,” she said. “More explosions could occur.”
Ms Joseph said it was impossible to predict whether any potential upcoming explosions would be bigger or smaller than the first one.
The eruption followed mandatory evacuation orders issued on Thursday for people who live near the volcano.
Officials planned to place them aboard cruise ships, send them to nearby islands or take them to shelters elsewhere in St Vincent that are outside the danger zone.
Roughly 16,000 people live in the red zone and will need to be evacuated, Ms Joseph said.
The pandemic could hamper evacuation efforts.
Prime Minister Ralph Gonsalves said in a press conference that people have to be vaccinated if they go aboard a cruise ship or are granted temporary refuge on another island.
He said two Royal Caribbean cruise ships are expected to arrive by Friday and a third one in the coming days, as well as two Carnival cruise ships by Friday.
Islands that have said they would accept evacuees include St Lucia, Grenada, Barbados and Antigua.
“Not everything is going to go perfect, but if we all co-operate … we will come through this stronger than ever,” Mr Gonsalves said.
He noted that he was talking to Caribbean governments to accept people’s ID cards if they do not have a passport.
“This is an emergency situation, and everybody understands that,” he said.
Mr Gonsalves added that he highly recommends those who opt to go to a shelter in St Vincent and the Grenadines, an island chain of more than 100,000 people, be vaccinated.
Emergency management teams have been going out to communities in the red zone and providing transportation to safer locations, including pre-arranged shelters, according to Ms Joseph.
“They know who doesn’t have transportation because all of this has been canvassed before,” she said, adding that those who board the cruise ship would not be taken elsewhere but would remain there for an unspecified period of time.
The volcano last erupted in 1979, and a previous eruption in 1902 killed some 1,600 people.
The eastern Caribbean is home to other active volcanoes.
Seventeen of the region’s 19 live volcanoes are located on 11 islands, with the remaining two underwater near the island of Grenada, including one called Kick ’Em Jenny that has been active in recent years.
The region’s most active volcano in recent years has been Soufriere Hills in Montserrat, which has erupted continuously since 1995, destroying the capital of Plymouth and killing at least 19 people in 1997.