A huge blast at a gasoline pipeline on Friday evening killed at least 66 people in Central Mexico and injured at least 76 others. The death toll could rise considering “many of the gravely wounded are battling between life and death,” the governor of Hidalgo state, Omar Fayad, said.

The explosion in Tlahuelilpan, a small town around 60 miles north of Mexico City, was caused by an illegal tap in the pipeline, according to state oil company Pemex. Dispatches from Tlahuellipan describe a gruesome scene of bodies piled on top of each other. Although officials said they are launching an investigation into the cause of the blast, Alejandro Gertz, Mexico’s attorney general, said “there was no doubt” it was the result of an illegal tap to steal fuel. Gertz also said that the investigation won’t be easy considering all of those who were closest to the site of the blast appear to have died.

Video posted online showed how moments before the blast, dozens of people had gathered at the illegal tap to fill buckets and other containers with fuel. Although there was military personnel on hand, video shows they stayed on the sidelines with officials explaining that the number of troops were not enough to stop all the people who had gathered at the site of the illegal tap.

The explosion came less than a month after Mexico’s new president, Andres Manuel Lopez Obrador, launched a crackdown on the rampant problem of fuel theft through illegal taps that cost the government billions of dollars a year. Pemex says its pipes were tapped an average of 41 times a day in the first 10 months of last year, which marked a 45 percent increase from the previous year. “Although it hurts a lot, we have to continue with the plan to end fuel theft,” the president said at a news conference. “We will not stop. We will eradicate this.” He also defended the army from claims that soldiers should have done more to prevent the tragedy in the first place.

On Twitter, Fayad called on citizens to not take fuel from illegally tapped lines. “What happened today in Tlahuelilpan should not be repeated,” he said. This was the deadliest pipeline explosion in Mexico in recent history after at least 27 people were killed in 2010 in a blast that officials also say was caused by an illegal tap of a pipeline.