A tsunami triggered by an underwater landslide from volcanic eruptions has killed at least 222 people and injured hundreds on the Indonesian islands of Java and Sumatra.
The tsunami struck late on Saturday night, almost without warning, along the rim of the Sunda Strait, Sutopo Purwo Nugroho, spokesman for the disaster mitigation agency, said.
Thousands of residents were forced to evacuate to higher ground. By Sunday, the disaster agency had raised the death toll to 222 from 168, with 843 injured and 28 missing.
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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.
Coastal residents reported not seeing or feeling any warning signs, such as receding water or an earthquake, before waves of 2-3 metres washed ashore, according to media.
Authorities said a warning siren went off in some areas.
The timing of the tsunami, over the Christmas holiday season, evoked memories of the Indian Ocean tsunami triggered by an earthquake on December 26 in 2004, which killed 226,000 people in 14 countries, among them Australians.
Oystein Lund Andersen, a Norwegian holidaymaker, was in Anyer town with his family when Saturday's tsunami struck.
"I had to run, as the wave passed the beach and landed 15-20 metres inland. Next wave entered the hotel area where I was staying and drowned cars on the road behind it," he said on Facebook.
"Managed to evacuate with my family to higher ground through forest paths and villages, where we are taken care of by the locals."
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 to December 25.
"Those who have evacuated, please do not return yet," said Rahmat Triyono, an official at the Meteorology, Climatology and Geophysics Agency.
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 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.
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.
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.
Dramatic TV footage showed the seconds when the tsunami hit a concert at the event and washed away the stage where the band, Seventeen, was performing.
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 9pm on Saturday and the tsunami struck at around 9.30pm (local time), according to the Meteorology Agency.
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.
Anak Krakatau is the island that emerged from the area once occupied by Krakatau or Krakatoa, which was destroyed in 1883. It first appeared in 1927 and has been growing ever since.
Malaysia and Australia both said they were ready to provide assistance if needed.