Wolf volcano erupts at Isabela island in Galapagos on May 25, 2015. [Photo/IC]

The park posted pictures showing lava pouring down the sides of the Wolf volcano, the Galapagos' highest point, while a dark plume estimated to be 10 km (6.4 miles) high, billowed overhead.

Wolf had been inactive 33 years, according to the park.

The lava is flowing down the volcano's southern face while the iguanas, officially an endangered species, inhabit the opposite side, the Environment Ministry said in a statement, adding it expected the animals to escape harm.