JAKARTA (REUTERS) - Indonesia's Merapi volcano erupted overnight, sending hot lava and ash down its slopes and prompting over 250 residents in the surrounding area to evacuate, the country's disaster mitigation agency (BNPB) said on Thursday (March 10).

Merapi spewed hot clouds - a mixture of ash and volcanic materials - that flowed 5km down its slopes between near midnight and 2am local time Thursday, Indonesia's geological agency said on Twitter.

BNPB said 253 residents around the volcano in the Yogyakarta province of Indonesia were evacuated, while ash blanketed some villages. No casualties were immediately reported.

The agency said the latest hot cloud was sent down the volcano's south-east slope at 7.33am local time on Thursday.

Potential dangers include more lava flows and hot clouds, BNPB said, warning people living within 7km of the volcano to keep away.

The 2,963 metre-high (9,721 feet) Merapi is one of Indonesia's most active volcanoes and was already on the country's second-highest alert level.

Located on the Pacific Ring of Fire, Indonesia has more volcanoes than any other country. Merapi last violently erupted in 2010, killing more than 350 people.

In December, the Semeru volcano in East Java province erupted, killing nearly 60 people.