Mount Merapi begins to spew lava as ash clouds cover towns on Indonesia's Java island

Mount Merapi, Indonesia's most active volcano, began spewing lava on Sunday, with ash clouds covering some towns on the Java island, a senior official said.

The rocks and lava flows formed by Merapi's eruption spread over a 2-kilometer (1.24-mile) area on the slopes of the volcano, the ABC News reported, citing Agus Budi Santoso, director of the Indonesian Geological Disaster Technology Research and Development Center.

Santoso said the eruption, which caused no casualties, resulted in the release of hot ash and gas clouds, which covered the sky in some towns.

Earlier on Wednesday, Indonesia's Volcano Science and Geological Disaster Reduction Center said in a statement that the Lewotobi Laki-Laki Volcano erupted, spewing ash up to 700 meters high, prompting 6,500 people in the region to seek refuge.

It also reported the eruption of the Semeru Volcano in the east of Java, which resulted in lava rivers, and the Ibu Volcano on Halmahera Island, which emitted ash up to 1,300 meters.

Indonesia, located in the Pacific Ring of Fire, is known for having the most seismic activity and volcanic eruptions in the world, with over 120 active volcanoes.