Six million people in southwest Colombia are without access to natural gas as of Wednesday, due to what authorities are calling a "thermal anomaly" possibly affecting pipelines.
Since midday, there had been "a total restriction on the natural gas service" in the western departments of Cauca and Valle del Cauca, utility Gases de Occidente said.
The crisis also affects five other departments in the center and southwest of the country, according to the mines ministry.
According to the pipeline company, Transportadora de Gas Internacional, the anomaly that shut down the gas pipelines could be "the product of an underground fire" in the area near a volcano and it could take a week to restore service.
Two-thirds of Colombia's 50 million people depend on the fuel for cooking and other uses.
"This brings... a crisis that we had not experienced for a long time," Jorge Ivan Ospina, the mayor of Cali, Colombia's third largest city, where more than 1.3 million users are affected, told the media.
Some residents switched to cooking with firewood and others stood in long lines to buy electric stoves, according to images shared on social media. In addition, several gas-powered public transportation vehicles have stopped working.