A volcano on Spain’s Atlantic Ocean island of La Palma erupted Sunday after a week-long buildup of seismic activity, prompting authorities to speed up evacuations for some 1,000 people.

The Canary Islands Volcanology Institute reported the eruption on Cumbre Vieja, which last erupted in 1971. Huge plumes of black-and-white smoke shot out from a point in the volcanic ridge where scientists had been closely following the accumulation of molten lava below the surface. Tinges of red could be seen at the bottom of the black jets that shot rocks into the air.

La Palma, with a population of 85,000, is one of eight islands in Spain’s Canary Islands archipelago. At their nearest point to Africa, they are 100 km (60 miles) from Morocco.

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After days of what scientists call “an earthquake swarm,” authorities on La Palma had already started to evacuate residents with reduced mobility Sunday shortly before ground broke open.

The area near the southern tip of the island is sparsely populated. Residents of the five nearby villages had already been told to be on alert and ready to leave their homes in case of an eruption.

A 3.8-magnitude quake was recorded before the eruption as vibrations from the seismic activity were felt on the surface.

The Scientific Committee of the Volcano Risk Prevention Plan said stronger earthquakes “are likely to be felt and may cause damage to buildings.” The committee of experts also noted that a stretch of the island’s southwest coast was at risk for landslides and rockfalls.

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