On Saturday, a natural gas pipeline operated by TransCanada Corp. exploded and subsequently started a massive fire in the Canadian province of Manitoba. The explosion and fire caused a shut-off of gas supplies to as many as 4,000 residents living in sub-zero temperatures.

TransCanada, the operator that applied for a permit to build the Keystone XL pipeline in 2008, said the fire was extinguished by Saturday afternoon, more than 12 hours after it started, but that the gas supply to several municipalities was shut off in order to repair the pipeline, according to ThinkProgress.

Thousands were left without heat, even as temperatures dropped below -20°C (-4°F), or below 34°C with the wind chill, CBC News reports. Flames reportedly reached about 200 to 300 meters (approximately 656 to 984 feet) in height.

The trouble began early Saturday when RCMP responded around 1:05 a.m. [local time] to a “loud explosion.”

Witnesses who live close to the scene said it was massive… The cause of the fire is under investigation.

The town of Niverville, Manitoba Deputy Mayor John Funk said that service could be lost for 24 hours to several days due to pipeline repairs. The rural municipality of Hanover, Manitoba said that the power outage could last between 24 and 72 hours.

TransCanada Corp. has been pushing for approval of its Keystone Pipeline, which began transporting oil to the US Gulf Coast through its southern leg this week. There have been conflicts of interest in the relationships between Keystone lobbyists and United States officials, and many are concerned with Keystone’s environmental review.

The company is still awaiting approval from the State Department for a permit for its northern leg, which would transport dirty oil sands crude from Canada to the US Gulf Coast to be refined and shipped overseas.

In November, the consumer rights group Public Citizen released a report detailing construction problems and code violations related to Keystone’s southern leg. In 250 miles of pipeline in the southern segment, there were at least 125 issues. According to the report, “There have been numerous ‘anomalies’ identified along the route, including dents, welds and other problems.”

The Wall Street Journal recently released a report stating that high-tech monitors used by energy companies often miss oil leaks in pipelines.

According to ThinkProgress, the WSJ examined Pipeline and Hazardous Materials Safety Administration data for 251 pipeline incidents occurring over the past few years and found that residents and company employees are 3 times more likely to detect pipeline leaks than the very monitoring technology that companies claim makes their pipelines safe and hinders environmental disasters.

Alisha is a writer and researcher with Ring of Fire. You can follow her on Twitter @childoftheearth.