Costly warning systems installed across Asia since the deadly 2004 tsunami did nothing to save villagers on these remote Indonesian islands who saw homes and loved ones swept away by a giant wave this week.
Such systems can be effective for people living hours away from where a tsunami is forged but are often unable to help those most at risk. A three-metre wave struck the Mentawai islands on Monday just minutes after a massive earthquake offshore, killing more than 400 and destroying hundreds of homes in 20 villages.
There are questions about whether Indonesia's system was working properly. Even if it was, a tsunami generated by an earthquake so close to shore can reach land long before there is a chance to raise an effective warning, experts say.
Piatoro, a coconut farmer on the wave-battered island of Pagai Selatan, said he and his family ran toward higher ground when the water slammed into their home, but it was too late. The water snatched his feet from under him and he was sucked under the waves, tumbling over and over. His wife was torn from him.
“I felt like I was boneless,” Piatoro (49) said on Friday as he sat alone on a hospital mat, skin scraped from his calf and stitches on a foot wound. It was not clear if his wife had survived.
Disaster response officials believe the final death toll could exceed 600, with many victims sucked out to sea as the tsunami receded
Elsewhere in the disaster-prone archipelago, the nation's most active volcano, Mount Merapi in central Java, was spewing lava and searing gas, after an eruption on Tuesday killed 34 people.
Volcanologist Heru Suparwoko said the clouds were “definitely dangerous” for people who had refused to obey orders to evacuate the danger zone.
Some 50,000 people have fled to temporary shelters but many are returning to their fields on the volcano during the day, despite the threat of another deadly eruption.