A gas tank truck exploded outside a maternity and children's hospital in Mexico City on Thursday morning, leaving much of it in ruins.
At least two people were killed and 56 injured, said Claudia Dominguez, spokeswoman for Mexico City's civil defense agency. Officials earlier had said at least four and as many as seven had been killed at the explosion site at the Maternity Hospital of Cuajimalpa, according to the Mexican newspaper El Universal.
Mexico City Mayor Miguel Angel Mancera put the number of injured at 66, with 22 of them in serious condition.
El Universal also reported that the truck's driver and his two helpers are among the injured, according to the municipality's secretary of state, Héctor Serrano, and are being detained while authorities "examine their responsibility."
Reforma, a daily newspaper in Mexico City, said that the Mexican Army is on-site searching for any more victims of the blast and the Red Cross has reported the transfer of nine infants to three hospitals.
“According to the report I have of the injured, the majority of the injuries are from glass, the explosion caused a variety of glass to hit and cut people,” Angel Mancera, said in an interview according to Mexico’s Reforma newspaper.
Thirty-five-year-old Felicitas Hernandez wept as she frantically questioned people outside the mostly collapsed building, hoping for word of her month-old baby, who had been hospitalized since birth with respiratory problems.
"They wouldn't let me sleep with him," said Hernandez, who said she had come to the city-run Maternity and Children's Hospital of Cuajimalpa because she had no money.
The explosion occurred when the truck was making a routine, early morning delivery of gas to the hospital kitchen and gas started to leak. Witnesses said the tanker workers struggled frantically for 15 or 20 minutes to repair the leak while a large cloud of gas formed.
"The hose broke. The two gas workers tried to stop it, but they were very nervous. They yelled for people to get out," said Laura Díaz Pacheco, a laboratory technician.
"Everyone's initial reaction was to go inside, away from the gas," she added. "Maybe as many as 10 of us were able to get out ... The rest stayed inside."
Workers on the truck yelled: "Call the firefighters, call the firefighters!" said 66-year-old anesthesiologist Agustin Herrera. People started to evacuate the hospital, and then came the massive explosion that sent up an enormous fireball and plumes of dust and smoke.
Herrera saw injured mothers walking out carrying babies. He said there had been nine babies in the 35-bed hospital's nursery, one in very serious condition before the explosion.
The blast occurred around 7:15 a.m. local time, and it leveled some 40 percent of the hospital.
Television images showed much of the hospital in western Mexico City collapsed, with firefighters trying to extinguish fires. Mancera said the heaviest damage was near the hospital's loading dock.
The area remained cordoned around the hospital to facilitate the work of the emergency services.
A hundred soldiers have been sent to the blast site to aid in rescue operations, and a spokesman for the Mexican Army said that they will also open the city’s central military hospital to treat the wounded if necessary.
Injured and bleeding, mothers carrying infants fled from a maternity hospital shattered by a powerful gas explosion on Thursday, and rescuers swung sledgehammers to break through fallen concrete in hunt for others who may have been trapped.
Ismael Garcia, 27, who lives a block from the hospital, said "there was a super explosion and everything caught on fire."
Garcia ran to the hospital and said he and others made their way to the nursery. "Fortunately, we were able to get eight babies out," he said.
Rafael González of the Red Cross said one 27-year-old man arrived at the agency's hospital with burns over 90 percent of his body, and he was transferred to another hospital.
President Enrique Peña Nieto expressed his sadness and support for the victims through his official Twitter account.
The hospital, located in a middle class neighborhood, is next to a school.
Includes reporting by the Associated Press.