More than 1,000 longshoremen walked off the job at New York and New Jersey ports on Friday morning, Jan. 29, effectively shutting down the terminals in a port system that receives nearly 30 percent of all cargo on the East Coast.

Traffic in and around the ports became gridlocked, with hundreds of truckers reportedly idling at the gates or inside the terminals.

Shortly after 3:00 p.m. EST, the Port Authority of New York and New Jersey gave its most recent update, stating on its website: “We appreciate your patience & cooperation as we safely & efficiently cleared the marine terminals. As we receive more info, we’ll keep you posted.”

PANYNJ had advised of the work stoppage shortly before 11 a.m. EST: “There is an apparent labor walk off at all PONYNJ terminals. No truck operations at this time.”

About an hour and a half later, the joint agency issued this update: “Due to the current work stoppage in the port, no new trucks will be allowed to queue on port roadways. Do not send trucks the Port at this time.”

According to PANYNJ, the striking workers are members of the International Longshoremen's Association, a key union at the ports in New York City and New Jersey.

A news report indicated that the job action was not sanctioned by the International Longshoremen's Association, making it a wildcat strike. An ILA spokesman said the walkout took many union officials by surprise, per the Associated Press.

 Another union official told NBC 4 New York that the job action could be traced to numerous grievances including concerns about the Waterfront Commission of New York Harbor's role in collective bargaining, regulations on time off after injuries and drug-testing protocols.

The affected terminals include Port Newark, the Elizabeth-Port Authority Marine Terminal, Port Jersey in Bayonne, Howland Hook Marine Terminal on Staten Island, and the Brooklyn Marine Terminal in the Red Hook section of Brooklyn.