EXPLAINER: Wide dangers ahead for Spanish volcanic island

MADRID (AP) — A small Spanish island in the Atlantic Ocean is struggling days after a volcano erupted, forcing the evacuation of thousands of people, and authorities are warning that more dangers from the explosion lie ahead.

Here is a look at the volcanic eruption on La Palma and its consequences:

WHERE DID THE VOLCANO ERUPT?

The eruption occurred Sunday afternoon on La Palma, one of eight volcanic islands in Spain’s Canary Islands archipelago, which is strung along Africa’s northwestern coast. It was the second volcanic eruption in 50 years for the island, which has a population of 85,000.

A 4.2-magnitude quake was recorded before the eruption. Huge plumes of black-and-white smoke shot out from the Cumbre Vieja volcanic ridge after a week of thousands of small earthquakes. Unstoppable rivers of molten lava, some up to 6 meters (20 feet) high, are now flowing downhill toward the ocean, engulfing everything in their path.

The Canary Islands are a volcanic hot spot popular with European tourists due to their mild year-round climate. Mount Teide, on the nearby island of Tenerife, is one of the world's tallest volcanoes and Spain's highest mountain. On La Palma, people live mostly from farming.

WHAT CAUSED THE ERUPTION?

Scientists had been closely monitoring a build-up of underground magma in La Palma for a week before the eruption, detecting more than 20,000 earthquakes — most too small to be felt. That is known as an “earthquake swarm” and can indicate an approaching eruption.

Three days before the eruption, the Canary Islands Volcanology Institute reported that 11 million cubic meters (388 million cubic feet) of molten rock had been pushed into Cumbre Vieja.

After the 4.2-magnitude earthquake, two fissures belched bright red magma into the air. The lava flowed in...