Lava flows from an eruption of a volcano near El Paso on the island of La Palma in the Canaries, Spain, Sunday, Sept. 19, 2021. Lava continues to flow slowly from a volcano that erupted in Spain’s Canary Islands off northwest Africa. The head of the islands' regional government says Monday he expects no injuries to people in the area after some 5,000 were evacuated. (Europa Press via AP)

Lava flows from an eruption of a volcano near El Paso on the island of La Palma in the Canaries, Spain, Sunday, Sept. 19, 2021. Lava continues to flow slowly from a volcano that erupted in Spain’s Canary Islands off northwest Africa. The head of the islands' regional government says Monday he expects no injuries to people in the area after some 5,000 were evacuated. (Europa Press via AP)

LA LAGUNA, Spain — Giant rivers of lava tumbled slowly but relentlessly toward the sea on Monday after a volcano erupted on a Spanish island off northwest Africa, with prompt evacuations helping to avoid casualties.

Long fingers of fiery red lava slid down hillsides with white smoke billowing from their leading edges as they swallowed up houses, gardens and swimming pools in a trail of destruction across the verdant countryside.