A volcano on Spain's La Palma island began ejecting lava again on Monday after a lull, while hundreds of people in coastal villages hunkered down in anticipation of lava emitted in previous days reaching the sea and releasing toxic gas.

Spurts of vivid lava emerged from the Cumbre Vieja volcano in the early evening and snaked down the dark mountainside after a period of several hours without explosions, according to witnesses.

The hiatus and new explosions came eight days after lava started pouring from the mountain range on the island, which neighbors Tenerife in the Canary Islands archipelago off North Africa.

"Activating and deactivating is logical, natural in the evolution of Strombolian volcanoes," said Miguel Angel Morcuende, director of the Pevolca response committee, referring to the type of violent eruption that emits incandescent dust.

Since September 19, black lava has been slowly flowing down the volcano's western flank toward the sea, destroying more than 500 houses as well as churches and banana plantations, according to the European Union's Copernicus disaster monitoring program.

On Monday, two tongues of the superheated black lava were rounding a hill to the west of the small town of Todoque, less than a kilometre from the Atlantic, but authorities said they could not be sure when it might reach the sea.

Still, about 300 local residents in the coastal areas of San Borondon, Marina Alta and Baja and La Condesa have been confined to their homes as the moment of contact between the lava and the sea is likely to trigger explosions and emit clouds of chlorine gas.

No fatalities or serious injuries have been reported, but about 15 percent of the island's banana crop could be at risk, jeopardizing thousands of jobs.

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