LA PALMA, Spain (Reuters) – Lava poured from an erupting volcano on the Spanish island of La Palma for a fourth day on Wednesday, blanketing houses and fields, a day after people with homes on the path of the molten rock were allowed back briefly to recover belongings.

Overnight, magma towers erupted into the sky and sprayed fiery material onto the Cumbre Vieja volcano’s flanks.

The volcano was seen earlier in drone footage. It flowed westwards towards the coast in three large tongues. They incinerated everything they came across, even a school.

According to the Canary Islands’ Vulcanology Institute, there was an increase in the volcanic’s seismic activity during the night of Tuesday through Wednesday.

The institute stated that seismic activity was “an indicator for the intensity of strombolian explosion activity” late Tuesday. Strombolian can be used to describe volcanic eruptions that explode violently and eject incandescent material.

Copernicus Emergency Management Service reported that the volcanic lava had reached an area of 154 ha (0.59 sq mile) within the cities of El Paso (and Los Llanos de Aridane).

Since the eruption of Sunday’s Cumbre Vieja volcano on Sunday, unstoppable flows have been steadily burning down houses and covering fields.

Nearly 6,000 residents of the island’s 80,000 inhabitants have been evacuated. Residents living along the path were allowed to go back inside their homes briefly for the purpose of recovering belongings.

Two tongues of blacklava carved a destructive swathe across the landscape, but no injuries or fatalities have been confirmed. Drone footage showed the two tongues cutting through the terrain as they moved down the volcano’s west flank toward the sea.

Experts believe that more explosives could be triggered if the lava touches the sea. The two-nautical mile zone around the area is being closed by marine officials as a precaution.

Although the lava flow had been expected to reach shore Monday night, its speed has dropped.