The US Department of Transportation (DOT) announced Monday it had fined Southwest Airlines $140 million over operational failures during last year’s “holiday meltdown” that stranded more than two million passengers. The civil penalty was leveled against the airline for “numerous violations of consumer protection laws during and after the operational failures that cancelled 16,900 flights,” the DOT said in a statement. The airline’s failures came during an extreme cold snap last December — accompanied by heavy snowfall — that caused travel chaos for millions of Americans over Christmas and New Year. A DOT investigation found that Southwest Airlines had violated consumer protection laws by failing to provide adequate customer assistance, update flight statuses and issue prompt refunds to people affected by the disruptions. The $140 million payment is 30 times larger than any previous fine for consumer protection violations, according to the DOT. It comes on top of more than $600 million already provided in refunds and reimbursements. “Today’s action sets a new precedent and sends a clear message: if airlines fail their passengers, we will use the full extent of our authority to hold them accountable,” US Transportation Secretary Pete Buttigieg said in a statement. “Taking care of passengers is not just the right thing to do — it’s required, and this penalty should put all airlines on notice to take every step possible to ensure that a meltdown like this never happens again,” he added. In addition to the $140 million fine, the DOT said it had ordered Southwest Airlines to establish a $90 million compensation scheme “for future passengers affected by significant delays and cancellations.”