Indonesian and Sri Lankan authorities struggled Wednesday to reach survivors of deadly floods in remote, cut-off areas, as the death toll from the disaster that has struck four countries rose to more than 1,300.
In Indonesia, survivors of devastating floods and landslides are growing frustrated with the pace of rescue operations and aid delivery.
Humanitarian groups said the scale of the challenge was almost never seen before, even for a country that has faced no shortage of natural disasters.
Monsoon rains and two rare tropical storm systems, sometimes known as cyclones in the region, brought record-breaking flooding to Sri Lanka and parts of Indonesia's Sumatra, southern Thailand, and northern Malaysia last week.
In Indonesia, the death toll rose to 753 on Wednesday, but the number of missing people also rose to 650.
The rising figures reflect information that is slowly coming in because many areas are either physically cut off by flood damage or isolated by power and communication failures, or both.
"Responding logistically is very challenging," said Ade Soekadis, executive director of Mercy Corps Indonesia, an aid group.
"The extent of the damage and the size of the affected area is truly enormous."
The group is hoping to send hygiene equipment and water to Jakarta and locally.
He said reports of food and water shortages were already "very worrying" and the situation would become "even more difficult" over time.
- 'Like an earthquake' -
At an evacuation center in Padan, 52-year-old Renaro Waruwu told AFP he was "disappointed" by the government's lack of immediate response and the slow arrival of aid.
"Some people waited a day and night before getting help, so they couldn't be rescued," he said, surrounded by evacuees sitting on mats on the floor of a shelter in the hall.
He added, "I'm frustrated, it doesn't need to be said twice. The response wasn't quick enough."
Like many, he described the floodwaters and landslide as a disaster unlike anything he'd ever experienced before.
Weeping loudly, he said, "It came like an earthquake... I thought, 'Well, if I'm going to die, it doesn't matter.'"
He managed to escape the rising waters, but his neighbors were buried alive under the rubble.
In shock, he couldn't even eat when he arrived, and food has been hard to come by since, although vegetables that arrived on Tuesday offered "a glimmer of hope," he said.
Nearby, 37-year-old Hamida Telambounua said her entire kitchen was swept away by the floodwaters.
She said, "My heart... It was the first time I've seen such a flood."
Her home was completely destroyed, along with everything except the few things she took with her when she left.
"It's hard to imagine what will happen next. Maybe as long as we're here, everything will be fine, but afterward... I don't know what will happen."
The weather system in Indonesia also brought heavy rains to Thailand, killing at least 176 people, and to Malaysia, where two people died.
Sri Lanka 'Open' to Tourists -
Although flooding is common in Asia during the monsoon season, climate change is making heavy rainfall events more frequent because a warmer atmosphere holds more moisture.
Warmer oceans can also turbocharge storm systems.
A separate weather system, Cyclone Ditwah, brought heavy rain, deadly flooding, and landslides to much of Sri Lanka last week.
At least 465 people were killed, and officials estimate the cost of the disaster at up to $7 billion.
"Our initial estimate is that we will need about $6 to $7 billion for reconstruction," said Prabhat Chandrakirti, Commissioner-General of Essential Services.
Another 366 people are missing, including in some of the hardest-hit areas that remain largely inaccessible.
Chandrakirti said that existing laws, which allow a person to be declared dead only after being missing for six months, could be shortened to expedite the issuance of death certificates.
The government has said it will provide families with 25,000 rupees ($83) to help clean their homes. Those who have lost their homes will receive up to $8,000.
More than 1.5 million people have been affected, of whom more than 200,000 are in government shelters.
Despite the disaster, the tourism-dependent country welcomed a luxury cruiseliner to Colombo Port on Tuesday, officials said.
The country's tourist board said the arrival "sends a clear message to the world: Sri Lanka is safe, open, and ready to welcome visitors once again."