include Andesite, Dacite, and Basalt; with minor indications of Trachyte. The island had reached a maximum elevation of before its collapse during the 2018 eruptive event. Volcanic activity The volcano's most recent eruptive episode began in 1994. Quiet periods of a few days have alternated with almost continuous Strombolian eruptions since then. Hot gases, rocks, and lava were released in an eruption in April 2008. Scientists monitoring the volcano warned people to stay out of a zone around the island. On 6 May 2009, the Volcanological Survey of Indonesia raised the eruption alert status of Anak Krakatoa to Level 3. An expedition to the volcano revealed that a wide lava dome was growing in its crater. In January 2012, volcanologists at the University of Oregon warned that a tsunami caused by flank collapse of Anak Krakatoa was likely, as it had formed on the steep eastern slope of the large caldera formed by the 1883 explosive eruption. 2018 eruption and aftermath A new eruptive phase was observed starting in June 2018; and on 15 October 2018, Anak Krakatau had a strong Strombolian to weak Vulcanian eruption that sent lava bombs into the water. An eruption of the volcano on 22 December 2018 caused a deadly tsunami, with waves up to five meters in height making landfall. On 31 December 2018, the disaster agency stated the tsunami's death toll was 437, with 14,059 injured. The tsunami affected more than 300 kilometers (186 mi) of coastline in Sumatra and Java and 40,000 people were displaced. This made the eruption the second deadliest volcanic eruption of the 21st century to date. Cone collapse—with tsunami generation—was considered a potential hazard immediately before the eruption. Scientists had modeled the possibility six years before the event, and had identified the western flank as the section of the volcano most likely to fail. Following the December 2018 eruption, it was believed that the southwest sector of the volcano, including the summit, had collapsed during the eruption, triggering the tsunami. On 23 December, this was confirmed by satellite data and helicopter footage, with the main conduit seen erupting from underwater, producing Surtseyan-style activity. The volcano lost over two-thirds of its volume due to this event, and its elevation above sea level was reduced from to just . Satellite radar observations showed that by 10 January 2019, the volcano had continued to form, with further eruptions beginning to re-model