A terrifying pyroclastic flow was seen roaring down the slopes of Mount Etna yesterday.

Footage shows the volcanic eruption, with thick ash plumes billowing into the sky on June 2.

The National Institute of Geophysics and Volcanology (INGV) in Italy said that volcanic activity picked up in the early hours of the morning had continued with strombolian explosions. It reported there was 'growing intensity'.

They added: 'Over the past few hours, the falling of a little thin ash has been flagged in the Piano Vetore area.'

Officials at the INGV said a pyroclastic flow - an avalanche of burning ash careening down the slopes at a fast-pace and high-density - was 'probably produced by a collapse of material from the northern flank of the South-East Crater'.

A red aviation warning was issued by the Volcanic Ash Advisory Centre Toulouse before being downgraded to orange.

The President of the Sicilian Region, Renato Schifani, said experts had assured him there was 'no danger to the population' as the pyroclastic flow did not extend beyond the Valley of the Lions, a popular tourist area.

Mount Etna, at 11,013ft (3,357m), is the tallest active volcano in Europe.