Updated

Last week, Alaska Airline employees were filmed hurling customer suitcases onto a concrete road at San Jose International airport in an apparent contest to see who could throw a heavy piece of luggage the farthest.

The airline has since apologized for the incident but it's just the latest in a series of incidents where carrier employees have been caught mishandling customer bags.

But now, as millions of Americans entrust luggage carefully packed with gifts and trinkets to baggage personnel during the busy holiday travel, the Department of Transportation has a stern warning for airlines that try to skip out on reimbursing customers whose checked baggage was damaged while in transit.

On Nov. 25,  the DOT issued a notice to airlines after recent airport inspections “uncovered the fact that certain airlines routinely exclude liability for damage to specific parts of checked baggage.” Under current federal law, carriers are responsible for reimbursing damage incurred to handles, zippers, wheels and other exterior parts of luggage left in their care.

But the investigation found that airline baggage policies of several carriers state they won't reimburse passengers for any damage incurred --which is a direct violation of the law. In Sept., the federal agency investigated incidents among airlines at 16 different foreign and international airports and found that “certain airlines may be refusing to accept reports of such damage"-- meaning that customers who complained were simply turned away.

U.S. airlines are also required to make sure that gate agents and other employees that deal directly with customers are up to date on the new rules regarding damaged luggage and do not turn away travelers who try to file complaints with the carrier.

Airlines have until Jan. 9, 2016 to review and, if necessary, revise their checked baggage liability policies or else face possible fines and enforcement action from the Department’s Aviation Enforcement Office.