A tsunami following a volcanic eruption killed at least 168 people and injured 745 on the Indonesian islands of Java and Sumatra on yesterday night, officials and media said on Sunday.
Hundreds of buildings were destroyed by the wave, which hit the coast of southern Sumatra and the western tip of Java about 9:30 pm (1430 GMT) following the eruption of a volcano known as the “child” of the legendary Krakatoa, national disaster agency spokesman Sutopo Purwo Nugroho said.
Search and rescue teams were scouring rubble for survivors, with 168 confirmed dead, 745 people injured and 30 reported missing across three regions, he said.
TV images showed the seconds when the tsunami hit the beach and residential areas in Pandeglang on Java island, dragging with it victims, debris, and large chunks of wood and metal.
On Dec 26 in 2004, an Indian Ocean tsunami triggered by an earthquake killed 226,000 people in 13 countries, including more than 120,000 in Indonesia.
Dramatic video posted on social media showed a wall of water suddenly crashing into an open-air concert by pop group “Seventeen” — hurling band members off the stage and then flooding into the audience.
In a tearful Instagram post, frontman Riefian Fajarsyah said the band’s bassist and road manager had been killed.
Images of the aftermath of the tsunami in coastal areas show a trail of uprooted trees and debris strewn across beaches. A tangled mess of corrugated steel roofing, timber and rubble were dragged inland at Carita beach, a popular day-tripping spot on the west coast of Java.
Muhammad Bintang, who was at Carita beach when the wave hit, described a sudden surge of water that plunged the tourist spot into darkness.
“We arrived at 9 pm for our holiday and suddenly the water came — it went dark, the electricity is off,” the 15-year-old told AFP.
“It’s messy outside and we still cannot access the road.”
In Lampung province, on the other side of the strait, Lutfi Al Rasyid said he fled the beach in Kalianda city in fear for his life.
“I could not start my motorbike so I left it and I ran… I just prayed and ran as far as I could,” the 23-year-old told AFP.
The eruption of Krakatau in 1883 killed more than 36,000 people in a series of tsunamis. Anak Krakatau is the island that emerged from the area once occupied by Krakatau, which was destroyed in 1883. It first appeared in 1927 and has been growing ever since.
Saturday’s tsunami was the latest in a series of tragedies that have struck Indonesia, a vast archipelago, this year. Successive earthquakes flattened parts of the tourist island of Lombok, and a double quake-and-tsunami killed thousands on Sulawesi Island. Nearly 200 people died when a Lion Air passenger plane crashed into the Java Sea in October.
Authorities warned residents and tourists in coastal areas around the Sunda Strait to stay away from beaches and a high-tide warning remained in place through till Dec. 25.
“Those who have evacuated, please do not return yet,” said Rahmat Triyono, an official at the Meteorology, Climatology and Geophysics Agency (BMKG).
President Joko Widodo, who is running for re-election in April, said on Twitter that he had “ordered all relevant government agencies to immediately take emergency response steps, find victims and care for the injured”.
Vice President Jusuf Kalla told a news conference the death toll would “likely increase”.
Rescue workers and ambulances were finding it difficult to reach affected areas because some roads were blocked by debris from damaged houses, overturned cars, and fallen trees.
The waves washed away an outdoor stage where a local rock band was performing in Tanjung Lesung in Banten province, a popular tourist getaway not far from the capital, Jakarta, killing at least one musician. Others were missing.
The western coast of Banten province in Java was the worst-hit area, Nugroho told reporters in Yogyakarta. He said at least 35 people were reported dead in Lampung in southern Sumatra.
Authorities say the tsunami may have been triggered by an abnormal tidal surge due to a new moon and an underwater landslide following the eruption of Anak Krakatoa, which forms a small island in the Sunda Strait between Java and Sumatra.
“The combination caused a sudden tsunami that hit the coast,” Nugroho said but added that Indonesia’s geological agency was working to ascertain exactly how it happened.
He added that the death toll would likely increase.
Video footage posted to social media by Nugroho showed panicked residents clutching flashlights and fleeing for higher ground.
Indonesian authorities initially claimed the wave was not a tsunami, but instead a tidal surge and urged the public not to panic.
Nugroho later apologized for the mistake on Twitter, saying because there was no earthquake it had been difficult to ascertain the cause of the incident early on.
“If there is an initial error we’re sorry,” he wrote.
The wave swamped parts of the coast around the Sunda Strait, but was most damaging in Pandeglang district, on Java’s western tip, where at least 33 people died and 491 people were injured.
Three people died further north in Serang, while seven were killed in South Lampung, on Sumatra island.
Heavy equipment was being transported to badly-hit areas to help search for victims, Nugroho said, adding evacuation posts and public kitchens were being set up for evacuees.
Abu Salim, a member of the Tagana disaster volunteer group, said he helped evacuate victims in Banten province.
“We evacuated the victims who died and were injured, we took them to health clinics … Most of them suffered from broken bones,” he said, adding he feared more were missing.
Although relatively rare, submarine volcanic eruptions can cause tsunamis due to the sudden displacement of water or slope failure, according to the International Tsunami Information Centre.
According to Indonesia’s geological agency, Anak Krakatoa had been showing signs of heightened activity for days, spewing plumes of ash thousands of meters into the air.
The volcano erupted again just after 9:00 pm on Saturday, the agency said.
An eruption just before 4:00 pm on Saturday lasted around 13 minutes and sent plumes of ash soaring hundreds of meters into the sky.
# Around 250 employees of the state utility company PLN had gathered in Tanjung Lesung for an end-of-year event, company spokesman I Made Suprateka told Reuters. At least seven people were killed, and around 89 are missing, he said.
The dramatic TV footage showed the seconds when the tsunami hit a concert at the event and washed away the stage where local rock band Seventeen was performing.
“The water washed away the stage which was located very close to the sea,” the band said in a statement. “The water rose and dragged away everyone at the location. We have lost loved ones, including our bassist and manager…and others are missing.”
Coastal residents reported not seeing or feeling any warning signs, like receding water or an earthquake, before waves of up to two meters washed ashore, according to media.
But authorities said a warning siren went off in some areas.
Officials were trying to determine the exact cause of the disaster. Anak Krakatau, an active volcano roughly halfway between Java and Sumatra, has been spewing ash and lava for months. It erupted again just after 9 pm on Saturday and the tsunami struck at around 9.30 pm, according to BMKG.
The tsunami was caused by “an undersea landslide resulting from volcanic activity on Anak Krakatau” and was exacerbated by abnormally high tide because of the full moon, Nugroho said.
Ben van der Pluijm, an earthquake geologist and a professor in the University of Michigan, said the tsunami may have been caused by a “partial collapse” of Anak Krakatau.
“Instability of the slope of an active volcano can create a rock slide that moves a large volume of water, creating local tsunami waves that can be very powerful. This is like suddenly dropping a bag of sand in a tub filled with water,” he said.
Neighbouring Malaysia and Australia both said they were ready to provide assistance if needed.
Indonesia, one of the most disaster-prone nations on earth, straddles the so-called Pacific “Ring of Fire”, where tectonic plates collide and a large portion of the world’s volcanic eruptions and earthquakes occur.
Most recently in the city of Palu on Sulawesi island a quake and tsunami in September killed thousands of people.
Anak Krakatoa is one of 127 active volcanoes which run the length of the archipelago.