HERMOSILLO, Mexico (CNN) -- Parents in northern Mexico on Sunday began to bury the children who died in a horrific day care fire as Mexican authorities raised the death toll from the blaze to 41.
Maria Jesus Coronado Padilla mourns her 2-year-old daughter, Paulette Daniela Coronado Padilla on Sunday.
A large crowd of mourners attended a funeral for six of the victims Sunday afternoon in Hermosillo, about 200 miles (320 kilometers) south of the U.S. border. The cause of Friday's fire at ABC Day Care wasn't known, but investigators concluded that the fire didn't start inside the building, said Eduardo Bours, the governor of Sonora state.
Neighbors described parents arriving at the day care center completely desperate on Friday, seeing it engulfed in flames and knowing there was no way to get the children out. The building had two doors, one of which was padlocked shut, and windows were too high for the children to reach, officials said.
Some parents rammed their vehicles into the building to try to free the trapped children, witnesses told CNN. Watch parents gather at site of fire »
"When we went out and ran towards the nursery, teachers already had many children outside, those who could walk properly," said one man at the scene, who did not give his name. "A pickup truck broke down the walls. The dad of one of the kids broke down one of the walls with his car driving in reverse, and that helped us a bit."
Others said they waited for hours for news of their children. Watch a town in deep shock »
"They didn't tell us anything, nothing, until like 6 p.m.," said Ofelia Vasquez, whose 4-year-old son Herman was in the building. She said she eventually was told he was at Chavez Hospital.
"We went there and we saw that he was badly burned, 75 percent of his body was burned," she said.
Herman Vasquez died after surgery, his mother said.
As of Sunday afternoon, 26 children remained hospitalized, 12 of them in critical condition, Sonoran authorities said. Another 10 children had been transported to other hospitals: eight to Guadalajara, one to Ciudad, Obregon, and two to Sacramento, California.
A team of 29 medical experts in Hermosillo was deciding if any more victims would be moved to the Shriners Hospital for Children in Sacramento, or elsewhere.
In addition, six adults were injured, Sonora spokesman Daniel Duran said.
"Without a doubt this is the worst disaster we've had," Bours told CNN.
President Felipe Calderon traveled to Hermosillo on Saturday. He arrived with Interior Secretary Fernando Gomez Mont and Health Secretary Jose Angel Cordova to get firsthand updates from doctors and investigators, the state news agency Notimex reported.
Calderon ordered the nation's attorney general to investigate the blaze.
Most of the victims died from smoke inhalation and not burns, Bours said. But the fire was serious enough for the roof to collapse, he added.
At the time of the blaze, 142 children were inside the ABC Day Care. The day care is for children ages 2 to 4, but Bours confirmed that children even younger were among the victims.
All the children at the center had been accounted for by Saturday evening, Bours said.
A severely burned 3-year-old girl arrived Saturday at the Sacramento hospital -- where pediatric burn treatment is a specialty -- and was in critical condition, according to Dr. Tina Palmieri, assistant chief of the burn unit.
The child was burned over 80 percent of her body, the doctor told reporters. She said the hospital normally can save just over half of the children with burns that severe.
In Hermosillo, a large crowd gathered outside of the emergency entrance of the city's general hospital and many people consoled each other, video from the scene showed.
"They told me that this happened in a matter of five minutes," Hermosillo Mayor Ernesto Gandara told reporters after surveying the scene.