The eruption of Indonesia's Semeru volcano has killed at least 14 people and injured dozens, the disaster mitigation agency (BNPB) said on Sunday, as search teams looked for victims in a landscape covered in deep layers of ash.

Semeru, the tallest mountain on Java island, threw up towers of ash and hot clouds on Saturday that blanketed nearby villages in East Java province and sent people fleeing in panic.

The eruption severed a strategic bridge connecting two areas in the nearby district of Lumajang with the city of Malang and wrecked buildings, authorities said.

A BNPB official said in a news conference late on Sunday that 14 people had been killed. Fifty-six were injured and 1,300 have been evacuated.

Most injuries were burns, authorities said.

Semeru, more than 3,600 metres high, is one of Indonesia's nearly 130 active volcanoes. It erupted in January, causing no casualties.

Indonesia straddles the "Pacific Ring of Fire", a highly seismically active zone, where different plates on the earth's crust meet and create a large number of earthquakes and volcanoes.