LOS ANGELES (AP) — The dispute between dockworkers at the West Coast’s sea ports and their employers didn’t take a day off for the Martin Luther King Jr. holiday.

The two sides have been trying to negotiate a new contract for months, and as tensions have risen the rate that cargo is moving has slowed.

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On Monday, the operators of terminals at ports where dockworkers typically load and unload massive ocean-going ships ordered slimmed-down work crews.

A spokesman for the terminal operators said container ships would not be worked at 29 ports from San Diego to Seattle because crews must concentrate on trying to clear dockside yards already congested with containers.

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The dockworkers’ union says its members are being unfairly punished; employers say dockworkers are purposely slowing work to gain bargaining leverage.

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