Rescuers are searching for survivors after a deadly tsunami smashed into the coasts of several islands in Indonesia, killing at least 281 and injuring over 1,000 people.

Indonesia’s meteorological agency confirmed the eruption and collapse of part of Anak Krakatau, a volcano between Java and Sumatra, caused a 2-6m high tsunami that hit the rim of the Sunda Strait late on Saturday.

Locals and tourists have been warned to stay away from coastal areas over fears another volcanic collapse could cause a second tsunami.

Dozens remained missing from the disaster areas along the coastlines of western Java and southern Sumatra islands on Monday, and authorities fear the number could increase once they hear from all stricken areas.

Doctors worked to save the injured as hundreds of military and volunteer rescuers used heavy machinery and their bare hands to dig through debris in the hopes of finding survivors.

Indonesia tsunami:Rescue operation begins after devastating tidal wave Show all 25 1 /25 Indonesia tsunami:Rescue operation begins after devastating tidal wave Indonesia tsunami:Rescue operation begins after devastating tidal wave Debris littered a property badly damaged by a tsunami in Carita, Indonesia. The tsunami occurred after the eruption of a volcano around Indonesia's Sunda Strait during a busy holiday weekend, sending water crashing ashore and sweeping away hotels, hundreds of houses and people attending a beach concert AP Indonesia tsunami:Rescue operation begins after devastating tidal wave Damaged cars are seen among collapsed houses after a tsunami hit Banten, Indonesia, December 23, 2018 in this photo taken by Antara Foto. Antara Foto/Dian Triyuli Handoko/ via REUTERS ATTENTION EDITORS - THIS IMAGE WAS PROVIDED BY A THIRD PARTY. MANDATORY CREDIT. INDONESIA OUT. ANTARA FOTO Reuters Indonesia tsunami:Rescue operation begins after devastating tidal wave An aerial photo shows damaged buildings in Carita AFP/Getty Indonesia tsunami:Rescue operation begins after devastating tidal wave Relatives mourn at a health facility where the bodies of tsunami victims are collected EPA Indonesia tsunami:Rescue operation begins after devastating tidal wave A resident walks past a collapsed guesthouse after a tsunami hit the area at Carita beach in Pandeglang, Banten province, Indonesia, December 23, 2018. REUTERS/Stringer NO RESALES. NO ARCHIVES. STRINGER Reuters Indonesia tsunami:Rescue operation begins after devastating tidal wave epa07246244 Indonesian officers carry an injured person into an ambulance after a tsunami hit the Sunda Strait in Banten, Indonesia 23 December 2018. According to the Indonesian National Board for Disaster Management (BNPB), at least 43 people dead and 584 others have been injured after a tsunami hit the coastal regions of the Sunda Strait. EPA/TUBAGUS TUBAGUS EPA Indonesia tsunami:Rescue operation begins after devastating tidal wave An aerial photo shows damaged buildings in Carita on December 23, 2018, after the area was hit by a tsunami on December 22 following an eruption of the Anak Krakatoa volcano. - A volcano-triggered tsunami has left at least 168 people dead and hundreds more injured after slamming without warning into beaches around Indonesia's Sunda Strait, officials said on December 23, 2018 voicing fears that the toll was set to rise. (Photo by Azwar Ipank / AFP)AZWAR IPANK/AFP/Getty Images AZWAR IPANK AFP/Getty Indonesia tsunami:Rescue operation begins after devastating tidal wave epa07246251 A man walks among debris, past a damaged car, after a tsunami hit the Sunda Strait in Pandeglang, Banten, Indonesia, 23 December 2018. According to the Indonesian National Board for Disaster Management (BNPB), at least 43 people dead and 584 others have been injured after a tsunami hit the coastal regions of the Sunda Strait. EPA/ADI WEDA ADI WEDA EPA Indonesia tsunami:Rescue operation begins after devastating tidal wave A man reacts after identifying his relative among the bodies of tsunami victims in Carita, Indonesia, Sunday, Dec. 23, 2018. The tsunami occurred after the eruption of a volcano around Indonesia's Sunda Strait during a busy holiday weekend, sending water crashing ashore and sweeping away hotels, hundreds of houses and people attending a beach concert. (AP Photo/Fauzy Chaniago) Fauzy Chaniago AP Indonesia tsunami:Rescue operation begins after devastating tidal wave TOPSHOT - An aerial photo shows damaged buildings in Carita on December 23, 2018, after the area was hit by a tsunami on December 22 following an eruption of the Anak Krakatoa volcano. - A volcano-triggered tsunami has left at least 168 people dead and hundreds more injured after slamming without warning into beaches around Indonesia's Sunda Strait, officials said on December 23, 2018 voicing fears that the toll was set to rise. (Photo by Azwar Ipank / AFP)AZWAR IPANK/AFP/Getty Images AZWAR IPANK AFP/Getty Indonesia tsunami:Rescue operation begins after devastating tidal wave epa07246239 Dead bodies collected at a health facility after a tsunami hit Sunda Strait in Pandeglang, Banten, Indonesia, 23 December 2018. According to the Indonesian National Board for Disaster Management (BNPB), at least 43 people dead and 584 others have been injured after a tsunami hit the coastal regions of the Sunda Strait. EPA/ADI WEDA ADI WEDA EPA Indonesia tsunami:Rescue operation begins after devastating tidal wave Residents collect debris from their collapsed houses Reuters Indonesia tsunami:Rescue operation begins after devastating tidal wave A local health center officer covers a dead body Reuters Indonesia tsunami:Rescue operation begins after devastating tidal wave This handout from Indonesia's Social Affairs Ministry taken and released on December 23, 2018 shows damaged buildings and vehicles in Carita, after the area was hit by a tsunami on December 22 following an eruption of the Anak Krakatoa volcano. - A tsunami following a volcanic eruption killed 62 people and injured hundreds more as it slammed without warning into tourist beaches and coastal areas around Indonesia's Sunda Strait on the night of December 22, sending panicked holidaymakers and residents fleeing. (Photo by Handout / Indonesia Social Affairs Ministry / AFP) / -----EDITORS NOTE --- RESTRICTED TO EDITORIAL USE - MANDATORY CREDIT "AFP PHOTO / Indonesia Social Affairs Ministry" - NO MARKETING - NO ADVERTISING CAMPAIGNS - DISTRIBUTED AS A SERVICE TO CLIENTSHANDOUT/AFP/Getty Images HANDOUT AFP/Getty Indonesia tsunami:Rescue operation begins after devastating tidal wave A man inspects his house which was damaged by a tsunami, in Carita, Indonesia, Sunday, Dec. 23, 2018. The tsunami apparently caused by the eruption of an island volcano killed a number of people around Indonesia's Sunda Strait, sending a wall of water crashing some 65 feet (20 meters) inland and sweeping away hundreds of houses including hotels, the government and witnesses said. (AP Photo/Dian Triyuli Handoko) Dian Triyuli Handoko AP Indonesia tsunami:Rescue operation begins after devastating tidal wave Bodies of victims recovered along Carita beach are placed in body bags on December 23, 2018, after the area was hit by a tsunami on December 22 following an eruption of the Anak Krakatoa volcano. - A tsunami following a volcanic eruption killed 62 people and injured hundreds more as it slammed without warning into tourist beaches and coastal areas around Indonesia's Sunda Strait on the night of December 22, sending panicked holidaymakers and residents fleeing. (Photo by Semi / AFP)SEMI/AFP/Getty Images SEMI AFP/Getty Indonesia tsunami:Rescue operation begins after devastating tidal wave An Indonesian man looks at ruined vehicles EPA Indonesia tsunami:Rescue operation begins after devastating tidal wave epa07246112 A handout photo made available by the Indonesia's national disaster management (BNPB) shows a ruined car that was rolled over after a tsunami hit Sunda Strait, in Anyer, Banten, Indonesia, 23 December 2018. According to BNPB, at least 43 people dead and 584 others have been injured. EPA/BNPB / HANDOUT HANDOUT EDITORIAL USE ONLY/NO SALES BNPB / HANDOUT EPA Indonesia tsunami:Rescue operation begins after devastating tidal wave Indonesian men walk among debris EPA Indonesia tsunami:Rescue operation begins after devastating tidal wave Rescue team evacuate the body of a victim EPA Indonesia tsunami:Rescue operation begins after devastating tidal wave A ruined tractor sits in the water EPA Indonesia tsunami:Rescue operation begins after devastating tidal wave Survivors receive treatment at a hospital in Carita AFP/Getty Indonesia tsunami:Rescue operation begins after devastating tidal wave A resident walks past damaged houses AP Indonesia tsunami:Rescue operation begins after devastating tidal wave A soldier examines a local resident who was injured Antara Foto/Reuters Indonesia tsunami:Rescue operation begins after devastating tidal wave Damaged cars are seen among the debris after a tsunami hit the Sunda Strait in Indonesia EPA

The tsunami arrived with almost no warning and destroyed more than 700 buildings, from small shops and houses to villas and hotels.

Nearly 12,000 coastal residents have been forcibly evacuated to higher ground, with a high-tide warning extended to Wednesday.

The Indonesian Medical Association of Banten region said it has sent doctors and medical supplies and equipment and that many of the injured were in need of orthopedic and neurosurgery surgery. It said most patients are domestic tourists who were visiting the beach during the long weekend ahead of Christmas.

Disaster mitigation agency spokesman Sutopo Purwo Nugroho said Indonesia had no warning system for volcanoes and underwater landslides.

President Joko Widodo visited the area on Monday and said an alert system was needed.

“I’ve instructed the Meteorology, Climatology, and Geophysical Agency to buy a detection device or a system that would provide an early warning so that the residents can be spared,” he told reporters.

Indonesia tsunami: Horrifying moment deadly waves wipe out stage as band play

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.

On Monday, five more bodies were recovered around the hotel, including a little boy.

“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.”

Indonesia Tsunami: Volcano erupting

Anak Krakatau, which means child of Krakatau, has been spewing ash and lava for months. Sixty-four hectares (0.64 square km) of the southwest side of the volcano collapsed.

“This caused an underwater landslide and eventually caused the tsunami,” said Dwikorita Karnawati, head of the meteorological agency.

The vast archipelago, which sits on the Pacific “Ring of Fire”, has suffered its worst annual death toll from disasters in more than a decade. Earthquakes flattened parts of the tourist island of Lombok in July and August, and a double quake-and-tsunami killed more than 2,000 people on Sulawesi island in September.

Many of the affected areas are popular weekend getaways for residents of Jakarta, but foreigners were also visiting the area over the long holiday weekend as well.

Britain, Australia and Canada advised nationals to monitor the situation closely and the United States embassy said it was ready to assist if needed.

Indonesia, a vast archipelago of more than 17,000 islands and home to 260 million people, lies along the “Ring of Fire,” an arc of volcanoes and fault lines in the Pacific Basin. Roads and infrastructure are poor in many areas, making access difficult in the best of conditions.

The timing of the tsunami over the Christmas season evoked memories of the Indian Ocean tsunami triggered by an earthquake on 26 December, 2004, which killed 226,000 people in 14 countries, including more than 120,000 in Indonesia.