The death toll from a tsunami that hit the Indonesian islands of Java and Sumatra after a volcano erupted rose to at least 280, as rescuers searched for more victims.
On Saturday, giant waves crashed into coastal towns on the islands of Sumatra and Java, killing at least 281 people and injuring 1016.
It is thought that volcanic activity set off undersea landslides which in turn generated the killer waves.
Anak Krakatau erupted again on Sunday, spewing ash and smoke.
Video shot from a charter plane captured the magnitude of the volcanic event in the Sunda Strait, between Sumatra and Java.
Prime Minister Jacinda Ardern said New Zealand was ready to assist the government of Indonesia with relief and recovery efforts.
Ms Ardern has expressed her condolences to the people of Indonesia for the loss of life and damage.
She said her thoughts were with the victims and everyone affected by the tragedy.
President Joko Widodo has expressed his sorrow for the victims and urged people to be patient.
Rescue efforts are being hampered by blocked roads but heavy lifting equipment is being transported to badly hit areas to help search for victims.
The Sunda Strait, between the islands of Java and Sumatra, connects the Java Sea to the Indian Ocean.
The head of the National Disaster Management Agency, Sutopo Purwo Nugroho, held a news conference on Java.
"Recommendations from [the] Meteorology, Climatology and Geophysical Agency are that people should not carry out activities on the beach and stay away from the coast for a while," he said.
"The potential for a fresh tsunami is still possible because the volcanic eruption of Anak Krakatau continues to occur, potentially triggering tsunami."
Anak Krakatau, which formed in 1927 after the Krakatoa volcano eruption, has seen increased activity in recent months with people asked to avoid the area around its crater.
Saturday's tsunami struck at about 9.30pm local time, during a local holiday.
It hit several popular tourist destinations, including the Tanjung Lesung beach resort in the west of Java island.
Footage shared on social media showed a large wave crashing into a tent in the resort, in which popular Indonesian rock band Seventeen was performing. Members of the band were seen being swept away as the wave destroyed the stage.
In a tearful Instagram video, singer Riefian Fajarsyah said the band's bassist and road manager had died, and three other band members and his own wife were missing.
Red Cross official Kathy Mueller told the BBC: "There is debris littering the ground, crushed cars, crushed motorcycles, we're seeing buildings that are collapsed."
It appears that the main road into Pandeglang has been badly damaged, making it difficult for rescuers to reach the area, she added.
Eyewitness Asep Perangkat said cars and containers had been dragged about 10 metres.
"Buildings on the edge of [Carita] beach were destroyed, trees and electricity poles fell to the ground," he told AFP news agency.
Officials say more than 160 people were killed in Pandeglang - a popular tourist district on Java known for its beaches and national park.
Meanwhile, 48 were reported dead in South Lampung on Sumatra, and deaths were also reported in Serang district and Tanggamus on Sumatra. Officials fear the death toll could rise further.
Anak Krakatau has seen increased activity in recent months. Indonesia's geological agency says the volcano erupted for two minutes and 12 seconds on Friday, creating an ash cloud that rose 400 metres above the mountain.
It recommended that no-one be allowed within 2km of the crater.
After the tsunami struck, there was confusion over what had actually happened, with Indonesian disaster agency spokesman Sutopo Purwo Nugroho initially reporting it as a tidal surge.
He later apologised for his mistake, saying there had been confusion because there was no earthquake.
High seas as a result of the full moon might have contributed to the strength of the waves, the disaster management agency said.
The proximity of the volcano to the coast gave authorities very little time to act, Professor David Rothery from The Open University told AFP news agency.
"Tsunami warning buoys are positioned to warn of tsunamis originated by earthquakes at underwater tectonic plate boundaries," he said.
"Even if there had been such a buoy right next to Anak Krakatau, this is so close to the affected shorelines that warning time would have been minimal given the high speeds at which tsunami waves travel."
Adding to the anxiety on Sunday, a tsunami warning went off by mistake, causing widespread panic as people scrambled to reach shelters. A technical error is suspected.
Indonesia is prone to tsunamis because it lies on the Ring of Fire - the line of frequent earthquakes and volcanic eruptions that circles virtually the entire Pacific rim.
In September, more than 2000 people died when a powerful earthquake struck just off the central Indonesian island of Sulawesi, setting off a tsunami that engulfed the coastal city of Palu.
On 26 December 2004, a series of huge waves triggered by a powerful earthquake in the Indian Ocean killed about 228,000 people in 13 countries, mostly in Indonesia.
However, tsunamis caused by volcanic activity like this are less frequent.
- RNZ / Reuters / BBC