A man inspects the damage suffered by a building following a tsunami in Anyar, Indonesia. Photo / AP
Disaster teams in Indonesia reported at least 222 deaths Sunday after a tsunami slammed ashore near an erupting volcano, sweeping over fishing ports and hundreds of people at a holiday beach concert without warning.
Authorities warned the death toll could rise as they widened searches and treated nearly 850 people injured by the three-foot surge of water from the Sunda Strait, off the western tip of Java island about 96km from Jakarta.
The strait is the shadow of the rumbling Anak Krakatau volcano, which has been erupting since June. Indonesian seismologists initially speculated that a landslide - possibly undersea - may have generated the tsunami late Saturday.
The event also did not create tremors that normally put coastal residents on watch for tsunamis. Officials also issued no formal tsunami warnings.
Indonesia's Disaster Management Agency, which announced the death toll, said at least 28 people were reported missing, but also some areas had not been reached by rescuers.
More than 500 buildings were destroyed or heavily damaged as waves poured in from the Sunda Strait, which separates Indonesia's two most populated islands, Java and Sumatra.
"Data collection is still ongoing. It's likely that the number of victims and damages will rise," said Sutopo Purwo Nugroho, spokesman for Indonesia's national disaster agency.
PM shares condolences
Prime Minister Jacinda Ardern has expressed her condolences to the Government and people of Indonesia for the loss of life and damage following yesterday's tsunami which hit the Sunda Strait.
"My thoughts are with the loved ones of the victims and everyone affected by this tragedy," Jacinda Ardern said.
"On the behalf of the New Zealand Government and people, I express our sincere condolences to the families of the victims and to the people of Indonesia.
"This disaster falls in the wake of the significant earthquakes in Bali and Lombok, and an earthquake and tsunami in Central Sulawesi experienced by Indonesia in the last five months.
"As with those earlier disasters, New Zealand stands ready to assist the Government of Indonesia with relief and recovery efforts if requested," Jacinda Ardern said.
There are 343 New Zealanders registered in Indonesia.
At this stage, there has been no request for international assistance from the Indonesian Government.
Video posted on social media showed the tsunami crash through a concert by an Indonesian band named Seventeen. The stage lurched forward, toppling the band and their equipment into the panicked crowds.
Oystein Lund Andersen, a Norwegian witness who was on a family trip on the coast of the Anyer beach, wrote on Facebook that he saw the incoming wave. "Next wave entered the hotel area where I was staying and downed cars on the road behind it. Managed to evacuate with my family to higher ground through forest paths and villages, where we are taken care of by the locals. Were unharmed, thankfully," he wrote.
In a statement, Indonesian President Joko Widodo sent his condolences to those affected and said he dispatched emergency responders. Officials said heavy rescue equipment and emergency soup kitchens have been prepared. Oxfam said it was also dispatching help to the region.
Indonesia's volcanology and geology disaster mitigation center said there was an eruption of Anak Krakatau on Saturday night. Although there was a "300 to 1500 metre" ash cloud reported above the crater's peak, the center said, it was unclear whether the tsunami was directly caused by the eruption.
Igan Sutawijaya, a volcano and geological disaster expert, said the Sunda Strait is a disaster-prone area but the waves may not be directly linked to an eruption.
"My suspicion is that there was an landslide under the sea. Perhaps a trench crumbled," he told The Washington Post in a phone interview. "It doesn't make sense that it was caused by the eruption of the Krakatoa."
Saturday's tsunami followed a string of disasters in Indonesia. Earthquakes and tsunamis have destroyed homes, killed and displaced thousands in areas such as the Lombok island in July and the Central Sulawesi city of Palu in September.
A Lion Air plane crash also killed over 189 people this autumn, leading experts to suggest the country was experiencing "disaster fatigue."
Indonesia sits on the seismically active "ring of fire" in the Pacific Ocean.
The Child of Krakatoa, an island that emerged in the 1920s after the 1883 volcanic eruptions of the Krakatoa, hosts one of Indonesia's most active eruption sites.