Last month a truck was hijacked in Stockholm and used to plow through a crowd of people, killing four.
Bill Aboudi runs a support center for truckers and sits on an area security committee at The Port of Oakland.
"We're always on alert but this just makes us pay attention, we'll talk to our drivers and make sure everything is ok," said Aboudi.
The TSA report cites 17 truck ramming attacks worldwide since 2014, the vast majority in Europe.
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It reads: "Commercial vehicles-distinguished by their large size, weight and carrying capacity--present an especially attractive mechanism for
vehicle ramming attacks..."
The TSA warning indicates hijacking is just one possible method a terrorist could use to obtain a truck, others include buying or renting one.
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