FedEx has warned its drivers to be cautious as videos circulate of thieves breaking into trucks or carjacking delivery drivers.

The large delivery company sent a security alert to its nearly 7,000 independent package-delivery contractors on Thursday Dec. 7 asking them to prioritize the safety of drivers and have them secure their delivery trucks, the Wall Street Journal reported.

“This Peak season is showing an increase in unlawful activity, putting increasing concern on safety and security,” an alert viewed by WSJ said.

WSJ reported that many of these contractors are small businesses that buy their own trucks and hire their own drivers.

FedEx did not respond to USA TODAY's request for comment but a spokesperson told Fox13 it's constantly monitoring crime trends and adapting policies to prioritize safety.

"The safety and well-being of our team members and the security of our customers’ shipments are always our top priorities. We have rigorous safety and security programs in place and regularly issue reminders to our employees and service providers about the importance of both personal and vehicle safety," FedEx said in a statement to Fox13.

The company provided drivers with tips to remain safe, including ensuring windows and doors are locked whenever possible, remaining vigilant and alert to their surroundings and calling 911 if there is imminent danger, Fox13 reported.

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Truck robberies for delivery drivers on the rise

In recent weeks, there have been several robberies of delivery trucks nationwide. Last month, a swarm of people surrounded a FedEx semi-trailer, forced open the rear doors, and stole packages, in Memphis, Tennessee, Fox13 reported.

In late November, an Amazon truck driver was robbed at gunpoint while unloading packages in New Haven, Connecticut, NBC Connecticut.

NBC San Diego reported that multiple delivery truck were robbed in the county including one that was captured on video in Chula Vista around Thanksgiving.

WSJ reported that as more deliveries are being made during the holiday season, the end of the year typically sees a general increase of theft but it's still not clear if these robberies are higher-than-usual this year.

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