Haiti's injured earthquake victims suffered a potentially deadly setback after the US military suspended evacuation flights because of a dispute over medical care costs.

Flights that have carried more than 500 people with spinal injuries, burns and other wounds ended on Wednesday after the governor of Florida asked the government to share the financial burden on his state's hospitals.

"Apparently, some states were unwilling to accept the entry of Haitian patients for follow-on critical care," US Transportation Command spokesman Captain Kevin Aandahl told AFP.

"Without a destination to fly to, we can't move anybody."

Aid groups warned the row over money could cost lives.

"People are dying in Haiti because they can’t get out," Barth Green of Project Medishare for Haiti, a nonprofit group which has been evacuating about two dozen patients a day, told The New York Time s.

The US State and Defense Departments were working with Florida governor Charlie Crist and state authorities to try to fix the problem, said US Ambassador to Haiti Kenneth Merten.

The United States has spearheaded relief efforts since the 7.0-magnitude quake on Feb 12, which killed around 170,000 people, injured around 200,000 and left more than one million homeless.

The aid effort as a whole has, however, drawn criticism for a lack of coordination. Several leftist Latin American nations have accused US forces of occupying Haiti militarily instead of focusing on aid needs. Related article: Big business urged to help Haiti

Ecuadoran President Rafael Correa, who left Haiti on Saturday after a two day visit, highlighted what he called the "imperialism" of aid efforts.

"They donate first, but most of it goes back to them," he said at a joint press conference with Haiti's President Rene Preval, criticising both military aid efforts and those of foreign NGOs.

Quake-hit Haitians, many of whom are living in squalid makeshift tent camps, have also complained that the huge influx of relief has been slow to reach them on the ground.

The UN World Food Programme said it would open 16 fixed collection sites reserved for women on Sunday in a bid to reduce long lines at mobile distribution locations.

Many of handouts have turned into dangerous scrums where women and children are shoved aside. The sites in the capital Port-au-Prince allow female survivors to pick up supplies using coupons.

Tent camps outside the capital that the government said would ease the pressure on Port-au-Prince have finally begun to open, but for some the squalid conditions are too much.

Dieases rising

A rickety boat carrying 126 Haitian migrants was picked up earlier this week off the Turks and Caicos Islands, the first group known to have fled since the earthquake, police said. The islands are a frequent stopover point for Haitians seeking to land in the US state of Florida.

"The amount of people on board is indicative of the problem we may now face," the British dependency's marine police chief Neil Hall said.

Diseases such as diarrhea, measles, and tetanus were rising in the tent settlements, prompting UN agencies and Haiti's government to prepare a mass vaccination drive.

Survivors also face rising insecurity with reports of rape and violence plaguing the weak and vulnerable.

In a blow to efforts to rebuild, Port-au-Prince's iconic Iron Market, built in 1889, was ravaged by fire on Friday and left to burn for hours by overstretched firefighters. Related article: Historic Haiti market burns

Schools are also struggling to resume lessons, with most missing hundreds of students and teachers.

"It's a disaster. There were many deaths. I've lost irreplaceable teachers," said Marie-Marthe Paul, director of the Canape Vert school in Port-au-Prince.

Aid officials have warned that the reconstruction process in Haiti, already the poorest country in the Americas before the quake, will take decades.