Recently, the Japanese agency which monitors Sakurajima Volcano in Japan, issued a raised alert over the threat of a large scale eruption with pyroclastic flow / damaging ash fall for several km around the area.
This eruption is small compared to what they think MIGHT occur soon.
Mirrored with permission from:
http://www.youtube.com/watch?v=8GgUWhajC6s&feature=channel_video_title