The seaport in Oakland, California, appeared to have joined others on the West Coast in resuming its normal operations on Sunday night after work disruptions earlier in the day, officials said.

"We've got five vessels being loaded and unloaded, and another three scheduled for operations," Port of Oakland spokesman Mike Zampa said.

His tone had shifted markedly from earlier in the day when he said port officials were "bitterly disappointed" at labor slowdowns that were "just not right" after a tentative agreement was reached with maritime companies on Friday.

An arbitrator had ordered a return to work on the 7 p.m. night shift after finding that longshoremen in the San Francisco Bay Area took part in illegal work stoppages that included taking breaks at the same time, among other actions reducing productivity.

Employers dismissed those employees for the day.

Melvin Mackay, a spokesman for the local union branch that covers Oakland, did not return a call for comment.

It was not yet clear whether all terminals were operating normally, but it appeared that most were, Zampa said.

The Port of Oakland handled about 10 percent of cargo at West Coast docks in 2013, according to the association's most recent data.

Meanwhile, work at the other 28 West Coast ports was mostly back to normal, with additional orders for labor especially at the larger ports to make up for a backlog caused by a monthlong contract dispute.

A tentative deal was struck late Friday. By Saturday night, workers in Oakland and the other ports from San Diego to Seattle were starting to clear the backlog.

West Coast seaports handle roughly one-quarter of U.S. international trade, an amount worth about $1 trillion annually.

More than 1,000 dockworker assignments were filled Sunday at the Ports of Los Angeles and Long Beach, more than double the number of recent Sundays. More than 2,000 were expected to be filled on Monday, port officials said.

It will take several months for ports such as Los Angeles and Long Beach — the nation's largest — to clear the backlog, which swelled as the two sides quarreled over a new deal.

"There's a lot of work to do and a limited labor pool. But it's being distributed between the two ports and the cargo containers between both LA and Long Beach as equitably as possible," Phillip Sanfield said.