QUITO - About sixty people have been missing and 13 others were injured after southern Ecuador's Tungurahua volcano erupted violently, unleashing its highest level of activity since 1999, a local official said.

"The situation is indescribable. There are approximately 60 people missing in the highest-risk area, as well as seven wounded people who were taken to the city of Riobamba and six others wounded in Penipe," Penipe Mayor Juan Salazar told Ecuavisa television on Thursday.

The mayor said the areas were affected by lava and flames from the 5,029-meter (16,499-foot) volcano, located just 135 kilometers (83 miles) south of Quito.

"There was a very powerful explosion this morning, which produced incandescent rocks, ash and lava that devastated several areas," Salazar said.