A massive fire that broke out on the surface of the Gulf of Mexico on Friday has been extinguished, but the incident is raising questions about the risks of undersea pipelines.

Videos of a swirling, orange mass of flames surrounded by ocean waves went viral after a gas leak was reported near a platform used for offshore drilling by Pemex, Mexico’s state-owned oil company. The scene was made even more surreal by the presence of firefighting boats that were dwarfed by the inferno, but eventually succeeded at putting it out after about five hours.

Angel Carrizales, who heads the Mexican agency charged with regulating pipeline safety, tweeted that the incident “did not generate any spill.” That claim drew some skepticism, given that something other than water had to be present on the ocean’s surface for it to ignite.

Pemex said Friday that the company would “carry out a root cause analysis of this incident” and that no one had been injured. The company provided few other details about the leak.

On social media, many argued that the eerie and alarming scene of a burning ocean clearly demonstrated the inherent problems of allowing oil companies to tap into fossil fuel reserves from the ocean floor.

“Shocking new example of how dirty and dangerous offshore drilling is,” the Center for Biological Diversity wrote on Twitter, calling for a moratorium on new oil leases in the Gulf of Mexico.

The fire took place in an area known as Ku-Maloob-Zaap, which is home to Pemex’s most productive oil fields. According to Reuters, an internal incident report stated that an electrical storm and heavy rains had damaged key machinery before the early-morning leak. Workers used nitrogen to put out the flames, according to the report.

Although Ku-Maloob-Zaap produces more than 700,000 barrels of oil a day on average, Pemex has been seeing its overall output fall and is roughly $114 billion in debt, according to Bloomberg News. As a result, the company has not been able to invest in new extraction technologies.

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