A massive, lightning-sparked fire feeding on two oil storage tanks in the Cuban city of Matanzas raged out of control Saturday and injured at least 121, according to the country's health ministry.

Of the injured, 36 remained hospitalized Saturday evening, five of whom were in critical condition, the Ministry of Public Health said. At least 17 people were missing, according to Cuban state television.

An unidentified body had been found and officials were trying to identify it, the ministry said in a statement late Saturday.

The lightning was reported Friday night. Officials said it struck one tank and sparked a fire that spread to a second.

The office of President Miguel Díaz-Canel said roughly 1,300 people living near the fire at the Matanzas Supertanker Base have evacuated, with an additional 600 workers told to leave.

Five nearby neighborhoods in Matanzas, which is about 100 miles east of Havana, were being actively protected from the fire's impacts, it said.

Additional ambulances have responded to the scene to take care of any injured people, the office said.

Cuba's Ministry of Energy and Mines said Saturday morning that lightning was the culprit, and the government later released a satellite map showing a bright red cloud of thunderstorm activity over the province, also called Matanzas.

On Saturday a black plume of smoke rose over the province, and forecasters said it was possible smoke could reach as far as Key West, Florida.

The U.S. Embassy in Cuba said federal law authorizes an American response, including disaster relief. It said U.S. officials have been in touch with Cuban authorities.

On Twitter, Díaz-Canel thanked countries that have offered help.

"We express deep gratitude to the governments of Mexico, Venezuela, Russia, Nicaragua, Argentina and Chile, which have promptly offered material aid in solidarity in the the face of this complex situation," he said.

"We also appreciate the offer of technical advice from the US," the president added.

The two tanks on fire were part of a storage facility with six other tanks, all used as fuel for electricity generation.

Michelle Acevedo is a New York-based senior editor for NBC News.

Dennis Romero is a breaking news reporter for NBC News Digital.