A truck carrying natural gas exploded on Thursday in Peru's capital, killing at least two people and injuring 48 in an accident that Peruvian President Martin Vizcarra called a "tragedy."

The truck burst into flames after it hurtled off a ramp on a street in Lima, breaking a valve, leaking gas and igniting several nearby homes. At least 11 children were sent to local hospitals with severe burns, authorities said.

"Given the magnitude of the consequences, we can qualify this as a tragedy," Vizcarra told reporters.

Health Minister Elizabeth Hinostroza said more than 50% of the victims were in "very critical" condition, with burns covering more than 80% of their bodies.

Peru restricts the shipping of gas to homes and industry via pipelines, and relies heavily on trucks for distribution of the fuel.

The accident comes just days before a Sunday election to replace the country's Congress, which Vizcarra dissolved last year.