HERMOSILLO, Mexico (CNN) -- Two of the owners of the day-care center that burned Friday, killing 44 children, have resigned jobs they had with the government, they told reporters Tuesday.
On Monday, two girls lay flowers during a funeral of one of the 44 children who died in the day-care fire.
Antonio Salido, a functionary for the state of Sonora's secretary of urban infrastructure, and Alfonso Escalante, a sub-secretary of livestock farming, said they were resigning so that there would be no obstruction in the investigation into the cause of the fire.
Salido, speaking for both men, told reporters they had not used their government positions to obtain the day-care concession.
"We want to show you how deeply we feel about what happened in the terrible accident that occurred at ABC Day Care," he said.
"It passed the security measures and norms of operation required by the Mexican Institute of Social Security," he said, referring to the governmental organization that oversees the state-run school.
He noted that the institute's director, Daniel Karam Toumeh, said Sunday that the building had passed an inspection on May 26.
Abel Murrieta Gutierrez, the attorney general of Sonora, told CNN en Español that the investigation would not be affected by the fact that two of the owners worked for the government.
"It doesn't matter to us if they were or were not functionaries," he said.
Relatives of the victims and people seeking better security for day-care centers are planning to march Wednesday evening from near the day-care center to the government center.
The fire started Friday afternoon in an air-conditioning unit located in an adjacent warehouse, the attorney general of Sonora said Monday. Investigators are trying to determine whether the fire was caused by an overheated motor or deficiencies in its installation, Abel Murrieta Gutierrez said.
The fire then moved toward bookshelves on a wall shared with the building housing the center, which held 141 children and day-care workers, he added.
The two buildings also shared a roof, which contained a false bottom made of polyurethane. That overheated, emitting toxic fumes, he said.
As of Tuesday, 22 children remained hospitalized with burns.
One of them was the daughter of Raul Alvarez, who prayed Tuesday at an improvised altar outside the Children's Hospital in Hermosillo. "We went to see her this morning, and she was stable, the little girl," he said.
Hermosillo is the capital of the state of Sonora, about 200 miles (320 kilometers) south of the U.S. border in northwestern Mexico.
It has no hospitals that specialize in burns, so doctors here have been working to stabilize those most badly burned before sending them on for treatment in other cities. Watch a town deep in shock »
"The most important thing is not so much the burn, but stabilizing them, making sure the kidney is functioning, the lung is functioning, the liver is functioning, the brain is functioning," said Raymond Lopez, Sonora's health secretary.
CNN's Rey Rodriguez contributed to this story from Hermosillo, Mexico.
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