While families began to bury the dead, officials indicated the death toll could still rise.
The state and federal governments say they are covering medical and funeral costs.
A forensic technician works at the site where a fuel pipeline ruptured by suspected oil thieves exploded, in the municipality of Tlahuelilpan, state of Hidalgo, Mexico on January 19, 2019. "It was just as they were withdrawing that the explosion occurred". Some seemed to have covered their chests in a last attempt to protect themselves from the blast. A few corpses seemed to embrace each other in death.
It is believed fuel thieves drilled through the pipeline.
Pipeline owner Petróleos Mexicanos (Mexican Petroleum) known as Pemex, says "The explosion in Tlahuelilpan, Hidalgo was derived from the manipulation of a clandestine takeover for fuel theft in the Tuxpan-Tula pipeline".
President Andres Manuel Lopez Obrador has made cracking down on fuel thieves a priority, claiming that the government lost over US$3 billion in 2018 due to illegal fuel siphoning. The battle against gas theft has led to long lines at the pump and gasoline scarcity in much of the country.
"Far from stopping the fight. against fuel theft, it's going to become stronger, we'll continue until we've eradicated these practices", Lopez Obrador, who has said he will step up the security presence in sensitive areas, said.
A number of people at the scene told Reuters that local shortages in gasoline supply since Lopez Obrador launched a drive to stamp out fuel theft had encouraged the rush to the gushing pipeline.
Grupo de militares venezolanos llama a desconocer a Maduro
La sublevación de los uniformados se dio a conocer a través de las redes sociales , quienes instaron al pueblo a salir a protestar contra el gobierno de Nicolás Maduro , al que consideran ilegítimo.
Lopez Obrador has repeatedly been asked why soldiers deployed to guard the duct did not chase people away from the leak, and how quickly the pipeline was shut down after Pemex detected the rupture.
The government has said the practice cost the country about $3bn (£2.3bn) past year. Pemex Chief Executive Octavio Romero said an estimated 10,000 barrels of premium gasoline were rushing through the pipeline with 20 kilograms of pressure when it was ruptured.
Up to 800 people gathered to collect fuel from a 7-m (23-foot) gasoline geyser, officials said. They haven't been seen since.
"We want to at least find a cadaver", she said while weeping.
Wrapped in a blanket, Hugo Olvera Estrada said he had gone to six nearby hospitals looking for his 13-year-old son, who had joined the crowd at the fuel spill. There aren't enough trucks, however.
"Part of the blame goes to the people [at the ruptured pipeline] but the bigger blame lies with authorities who let them go there knowing it was unsafe", said Velasco, the farmer.
They then re-sell mostly to complicit gas stations. A couple of hours later, it erupted in flames in a powerful explosion. But in this fire there were no reported casualties.
Alejandro Gertz Manero, general prosecutor of Mexico, said Saturday night that the investigation has just started but that a "preliminary belief" is that static electricity from the clothing of people around the pipeline may have caused the blast.