Updated

A disaster official says hundreds of people have fled their villages along the slopes of Indonesia's most volatile volcano after it started belching smoke and ash.

Disaster mitigation agency spokesman Sutopo Purwo Nugroho says Mount Merapi on Java island rumbled as heavy rain fell around its cloud-covered crater early Monday.

He says the volcano unleashed a column of dark red volcanic material 1,000 meters (3,280 feet) high. The ash made the rain thick and muddy in several villages as terrified residents fled to safety.

He says the sound was heard 30 kilometers (18 miles) away, but an eruption did not occur and the volcano's alert level was not raised.

The 2,968-meter (9,737-foot) mountain is the most active of 500 Indonesian volcanoes. Its last major eruption in 2010 killed 347 people.