Only those who have received the COVID-19 vaccine will be able to safely evacuate from St. Vincent after the Caribbean island nation’s La Soufriere volcano erupted on Friday, Prime Minister Ralph Gonsalves said in a press conference Saturday.

Giving a press conference with his face visibly welling up with tears, the Vincentian prime minister explained that cruise ships had volunteered to transport the island’s residents to nearby Caribbean islands for shelter, but only vaccinated people would be allowed to board.

“The chief medical officer would be identifying the persons already vaccinated so that we can get them on the ship,” he told reporters.

He explained the cruise ships “don’t have enough personnel” to keep people on the ships, but can transport them.

The decision does not appear to be his, but rather was made by the neighboring island nations of Barbados, Grenada, Antigua and St. Lucia, which said they would only accept fully vaccinated refugees.

The island nation is home to some 100,000 people.

Last Thursday, the country began to take precautions, and had ordered the evacuation of homes in the northern parts of the island due to a possible risk that La Soufriere could erupt.

The volcano had been dormant since 1979, with its last eruption causing around $100 million in damages. In 1902, an eruption killed over 1,000 people.

The Friday eruption caused ash and smoke and plunged the neighboring area into near total darkness, blotting out the bright morning sun, said a Reuters witness, who reported hearing the explosion from Rose Hall, a nearby village.

Smaller explosions continued throughout the day, Erouscilla Joseph, director at the University of the West Indies Seismic Research Centre, told Reuters, adding that this kind of activity could go on for weeks if not months.

“This is just the beginning,” she said.

The eruption column was estimated to reach 10 km. (6 mi.) high, the seismic research center said. Ash fall could affect the Grenadines, Barbados, St. Lucia and Grenada.

Local media have in recent days also reported increased activity from Mount Pelee on the island of Martinique, which lies to the north of St. Vincent beyond St. Lucia.