Video report by ITV News Correspondent Juliet Bremner
Rescuers have been searching debris-strewn beaches for more victims of the deadly Indonesia tsunami which smashed into houses, hotels and other buildings along the Sunda Strait.
The waves which swept terrified people along the coastlines of western Java and southern Sumatra islands on Saturday night followed an eruption and possible landslide on Anak Krakatau, one of the world's most infamous volcanic islands.
At least 373 people are now confirmed to have died while more than 1,450 were left injured.
Aerial footage of Anak Krakatau volcano taken on Sunday
It comes as the Queen sent condolences to those affected by the tsunami.
In a message, she said: "Prince Philip and I were deeply saddened to learn of the loss of life following the devastating tsunami in Indonesia.
"We send our sincere condolences to all who have lost loved ones and those whose homes and livelihoods have been affected."
Dozens are missing from the disaster areas and the numbers could increase once authorities hear from all stricken areas.
The Indonesian Medical Association says it is sending more doctors and medical equipment and that many of the injured are in need of orthopaedic and neurosurgery expertise.
It says most patients are domestic tourists who were visiting the beach during the long holiday weekend.
It was the second deadly tsunami to hit Indonesia this year, but the one that struck the island of Sulawesi on September 28 was accompanied by a powerful earthquake that gave residents a brief warning before the waves struck.
On Saturday night, the ground did not shake beforehand to alert people to the oncoming wave that ripped buildings from their foundations in seconds and swept terrified concertgoers on a resort beach into the sea.
Dramatic video posted on social media showed the Indonesian pop band Seventeen performing under a tent on Tanjung Lesung beach at a concert for employees of a state-owned electricity company.
Dozens of people sat at tables while others swayed to the music near the stage as strobe lights flashed and theatrical smoke was released.
A child could also be seen wandering through the crowd.
Seconds later, with the drummer pounding just as the next song was about to begin, the stage suddenly heaved forward and buckled under the force of the water, tossing the band and its equipment into the audience.
The group released a statement saying their bass player, guitarist and road manager were killed, while two other band members and the wife of one of the performers were missing.
"The tide rose to the surface and dragged all the people on site,” the statement said. "Unfortunately, when the current receded, our members were unable to save themselves while some did not find a place to hold on."
Disaster agency spokesman Sutopo Purwo Nugroho said on Monday morning that 281 deaths had been confirmed and at least 1,016 people were injured.
The worst-affected area was the Pandeglang region of Java’s Banten province, which encompasses Ujung Kulon National Park and popular beaches, the agency said.
Indonesian President Joko "Jokowi" Widodo expressed his sympathy and ordered government agencies to respond quickly to the disaster.
"My deep condolences to the victims in Banten and Lumpung provinces," he said. "Hopefully, those who are left have patience."
Scientists, including those from Indonesia’s Meteorology and Geophysics agency, said the tsunami could have been caused by landslides — either above ground or under water — on the steep slope of the erupting Anak Krakatau volcano. The scientists also cited tidal waves caused by the full moon.
The 1,000ft-high Anak Krakatau, whose name means "Child of Krakatoa," lies on an island in the Sunda Strait between Java and Sumatra islands, linking the Indian Ocean and the Java Sea.
It has been erupting since June and did so again about 24 minutes before the tsunami, the geophysics agency said.