Indonesian volcano spews hot gas

Deadly Mount Sinabung on Indonesia's Sumatra island is again spewing hot ash kilometres into the sky.

The volcano in North Sumatra province on Wednesday sent gas and volcanic matter 4.5 kilometres to the east, said national disaster management agency spokesman Sutopo Nugroho.

"Residents are advised to remain alert."

The 2460-metre volcano has erupted intermittently since late 2013, displacing thousands of people.

Sixteen people were killed in early 2014 during an intense period of eruptions.

Indonesia sits on the Pacific Ring of Fire, an area known for seismic upheavals and volcanic eruptions.

The country is home to about 130 active volcanoes.