The scale of the fighting in the Iraqi town of Falluja last week is becoming clear as a shaky ceasefire takes hold.
A football field has been turned into a makeshift cemetery
A group of five international charities estimated that about 470 people had been killed, while hospital officials put the death toll at about 600.
Reuters television footage from Falluja showed corpses of children, women and old men lying in the street beside body parts no one has had time to collect.
"Hospitals and medical staff are overwhelmed," the five charities said.
They added that they were "asking desperately for blood, oxygen and antiseptics".
The group said that at a conservative estimate, about 1,200 had been wounded, according to Reuters, which did not name the aid agencies involved.
Residents of Falluja have reportedly been burying the dead in their gardens and a football field because it is too dangerous to go to the cemeteries on the outskirts of town.
Kifaya Ilawee fled the town when her neighbour's house was hit by a shell.
"I have lived in Falluja for 30 years. I have never seen anything like this, what we saw every day in Falluja last week," she told Reuters.
She is now living in Baghdad with 35 others who also fled the fighting.
Umm Samir left the town with her family on Saturday, London's Guardian newspaper reported.
She described "constant bombing" as US-led coalition forces battled insurgents during the week in Falluja, known as the city with 100 mosques.
US Brigadier General Mark Kimmitt said on Monday that about 70 coalition soldiers had been killed in Iraq in April, and that about 10 times that
number of Iraqis had been killed over the same period.
The US says most of the Iraqi dead were fighters.
Umm Samir, 62, says her family was originally pleased that the Americans had deposed Saddam Hussein.
But then the US troops began treating Iraqis "disrespectfully... as though we were beneath their feet," she told the Guardian.
American behaviour had helped provoke ordinary people to join the resistance, she said, adding that even she and her older sister wanted to join the fighters.
Sadr's militia is thought to have about 10,000 members
"When the Americans arrived there were only about 50 guerrillas," another Falluja resident, Nada Rabee, told Reuters.
"By the end of the week there were a few thousand. They are just making the situation worse."
A New York Times report corroborates these claims.
The US newspaper says that many people - perhaps tens of thousands - who did not consider themselves full-time resistance fighters were now prepared to join the insurgency.
Khalif Juma, a 26-year-old vegetable seller, told the newspaper he was angry about the US treatment of radical Shia religious leader Moqtada Sadr, for whom an arrest warrant has been issued.
"To be honest, we weren't like this before. But we're religious people, and our leader has been threatened," he told the newspaper.
"We would be ashamed to stay in our houses with our wives at a time like this."
He and his cousins have bought a crate of Kalashnikov rifles, he said.