On the 29th of December 1927, a submarine eruption started in the same position of Krakatau's mighty explosion of the 19th century. A new island named Anak Krakatau - "Child of Krakatau" rose above the water but the pumice and ash were quickly washed away by wave action as were the other two islands that followed. In August 1930, a fourth island emerged, erupting lava flows that resisted erosion.
Krakatau is directly above the subduction zone of the Eurasian Plate and the Indo-Australian Plate where the boundaries make a sharp change of direction leading to a weakening of the crust.
There were three volcanic cones on Krakatau: Rakata to the south, Danan to the north and Perboewatan also to the north.
Since the 1950s the island has steadily grown to a high point of around 980 feet (300m) above sea level and is still active with the latest eruption starting in April 2008 but an intense period of explosive eruptions began in 2009.
The following images were taken by Marco Fulle over the 4th to the 9th of June, 2009.
This is Anak Krakatau from the island of Rakata which is the main island of the Krakatoai group.
This is Anak during a tropical storm where lightning hits the crater. Lightning activity like this was also seen over the crater of the erupting Chaiten volcano.