Indonesian search and rescue teams on Wednesday plucked stranded residents from remote islands and pushed into isolated communities desperate for aid after a volcano-triggered tsunami killed over 400.
But torrential rains hampered their efforts and heaped more misery on the region as stunned residents waded through waist-deep water in parts of hard-hit Carita.
"Heavy rains caused a river to overflow and several places are flooded," national disaster agency spokesman Sutopo Purwo Nugroho said on Twitter.
"It's hampering efforts to evacuate people and help other survivors."
The disaster agency cautioned residents to stay clear of the coast as activity was still high at the rumbling Anak Krakatoa volcano, which sits in the middle of the Sunda Strait between Java and Sumatra islands.
A section of the crater collapsed after an eruption and slid into the ocean, triggering Saturday night's killer tsunami, officials have said.
The powerful waves struck without warning, washing over popular beaches and inundating tourist hotels and coastal communities on both sides of the strait — and leaving a trail of death and destruction.
Medical workers have warned that clean water and supplies were running low — stoking fears of a public health crisis — as thousands of displaced survivors cram shelters and hospitals. Many were left homeless by the killer wave.
The disaster agency has dispatched helicopters to drop supplies into a handful of hard-to-reach communities along the shattered coastlines.
Hundreds of residents still stranded on tiny islands in Sunda Strait are being airlifted or taken by boat to shelters.
Sniffer dogs are being used to find those still missing as grief-stricken relatives lined up at identification centres.
"We're starting to access the most isolated places hit by the tsunami," said senior disaster agency official Dody Ruswandi.
"The devastation there is pretty massive."
At the Tanjung Lesung resort, mangled remnants were clumped on the soggy ground — a jumble of metal, chairs and awning.
Elsewhere, cars and minibuses had been thrown against buildings, concrete walls shattered into small pieces and uprooted trees spread around.
A wooden sign that read "Good Times" lay on the ground.
The tsunami struck the resort as more than 200 workers from the state electricity company were watching pop band Seventeen perform.
The four-member group was hurled from the stage as the water slammed into the audience — only the band's lead vocalist survived.
Hundreds of Indonesian Red Cross staff and volunteers are delivering clean water, blanket, tarpaulins and other supplies, while it dispatched mobile medical units.
"Our teams are seeing many broken bones and broken homes, and people who are very shaken," said Arifin Hadi, head of disaster management at the Indonesian Red Cross.
"Indonesians have withstood a string of disasters this year and with them, so much loss and misery."
Jakarta has so far rebuffed offers of international aid, saying the disaster-prone country could handle the latest crisis.
On Wednesday, thousands prayed for loved ones at mass graves and mosques to mark the 14th anniversary of the 2004 Boxing Day tsunami.