Authorities have evacuated over 1, 200 residents from the slope of a volcano in Central Java as they have raised the alert level of the volcano to the second top alert, an official said on Wednesday.

Head of the Volcanology Agency named only Surono told Xinhua by phone that the status of Mount Dieng has been raised to the second top alert on May 29 and has declared an evacuation zone at one kilometer.

"So far the seismic activity of the mount still fluctuates. ( But) the process of forming energy tends to rise and the formation of gas also tends to increase," said Surono.

The agency has recommended evacuation of the people living around the slope.

"So far, the danger from the mount is the gas released from the crater," said Surono.

The National Disaster Management and Mitigation Agency has facilitated 1,179 evacuees, an official of the agency told Xinhua by phone. Foods and medicine have been sent to the site, the official said.

The evacuees have taken shelters at makeshift tents, school buildings and village office buildings, he said.

Mount Dieng is one of Indonesia 129 active volcanoes, according to the Volcanology Agency.