The death toll from a sudden volcanic eruption in Japan hit 48 on Wednesday as rescuers discovered 12 new bodies in previously unexplored areas of the ash-covered peak.

The figure makes the eruption of Mount Ontake, which was packed with hikers when it burst angrily to life on Saturday at lunchtime, the worst volcanic disaster in Japan for almost 90 years.

Up until Sunday 36 bodies had been found, but many of these remained on the ruptured mountain as toxic gas and the risk of further eruptions forced emergency workers to suspend operations.