Mount Merapi spews clouds of hot gas

JAKARTA, Indonesia (CNN) -- Indonesia's most active volcano is belching smoke and ash, signaling it may erupt.

Residents living near Mount Merapi have been told to get ready for an evacuation, although vulcanologists say there is no immediate danger. Several million people live in the vicinity of the volcano.

Intensified gas clouds and an earthquake measuring at least 4.0 would precede any eruption, experts said.

Earlier this week, officials raised the warning status of an eruption to the highest level of alert after lava began overflowing from the 2,968-meter (9,737-foot) volcano in central Java. On Thursday, residents were constructing dams to channel lava flow.

Merapi, which is about 250 miles (402 kilometers) east of Jakarka, erupted without warning in November 1994, killing 60 people.

Three years later, more than 8,000 villagers had to be evacuated after the volcano began spewing hot gas, ash and lava.

Merapi's most destructive eruption this century was in 1930, when 1,300 people were killed.