Survivors of Typhoon Haiyan in the Philippines are increasingly desperate for food, water and medical supplies, officials in affected areas say.
The official death toll stands at more than 2,000, though some reports say it could be as high as 10,000.
The UN says more than 11 million people may have been affected and some 673,000 displaced.
On Tuesday, eight people died when a wall collapsed as thousands of survivors mobbed a food warehouse.
Police and soldiers were unable to stop the looters, who took more than 100,000 sacks of rice from the government facility in Alangalang, Leyte, said Rex Estoperez, spokesman for the National Food Authority.
There were also reports on Wednesday of gunshots in the devastated streets of Tacloban, a city of 220,000 on Leyte island which is particularly badly affected.
Typhoon Haiyan - one of the most powerful storms ever recorded on land - hit the coastal Philippine provinces of Leyte and Samar on Friday.
It swept through six central Philippine islands before going on to kill several people in Vietnam and southern China.
Disaster management officials in the Philippines have put the confirmed death toll there at 2,275, with another 3,665 injured as of Wednesday. More than 80 people are listed as missing.
But speaking to CNN on Tuesday, Philippine President Benigno Aquino said the widely reported estimate that 10,000 people had been killed by the storm - known locally as Yolanda - was inaccurate and may have come from officials facing "emotional trauma".
But he said 29 municipalities had yet to be contacted to establish the number of victims there.
The president also warned that storms like Haiyan were becoming more frequent, and there should be "no debate" that climate change was happening.
He said either the world committed to action on climate change "or let us be prepared to meet disasters".
However, a congressman in Leyte told the BBC he believed the government was giving conservative estimates of the death toll "so as not to cause undue alarm".
"Just viewing the disaster's scope - its magnitude and the areas affected - we believe that the 10,000 figure is more probable," said Martin Romualdez. "As we start cleaning up we are finding more bodies."
The damage to Tacloban was "so massive in scale and so extensive in our areas that we literally would have to rebuild from scratch", he said, calling for greater co-ordination as aid to combat the rising "sense of hopelessness and desperation".
The head of the Philippines Red Cross, Gwendolyn Pang, also said she expected the official death toll to rise.
"Numbers are just coming in. Many of the areas we cannot access," she told Reuters.
Relief operations are being stepped up, but damage to transport links and continuing bad weather have hindered aid distribution.
The BBC's Jonathan Head in Tacloban says residents are becoming angry at the lack of progress and increasing breakdown in security.
Planes are arriving at the airport, but bringing little in and only taking people out, and there is little sign of a co-ordinated relief operation, he says.
But Philippine Interior Minister Mar Roxas told the BBC that relief efforts were on track.
"Our first priorities were, number one, to establish law and order; number two, to bring food and water to the people; and, number three, to recover the cadaver bags," he said.
"[Now] law and order has been stabilised, the supply of food and water is beginning - I'm not saying that we're anywhere near it - [but it] is beginning to be stabilised... and now we are concentrating on recovery of cadavers as well as on the distribution of the food and the relief that is coming in."
On Tuesday the UN launched an appeal for $301m (£190m) to help survivors. It has already released $25m to meet immediate needs.
The UN Office for the Co-ordination of Humanitarian Affairs (OCHA) says 11.3 million people are in need of vital goods and services, because of factors such as lack of food, healthcare and access to education and livelihoods.
The UK's Disasters Emergency Committee (DEC) has also launched an appeal.
US and British navy vessels are heading to the Philippines and several nations have pledged millions of dollars in aid.