Yellow Corp., one of the largest trucking companies in the United States, has halted its operations and is filing for bankruptcy, according to the Teamsters Union and multiple news reports.

The closure threatens the jobs of nearly 30,000 employees at the nearly-century-old freight delivery company, which generates about $5 billion in annual revenue.

After a standoff with the union, Yellow laid off hundreds of nonunion employees on Friday before ceasing operations on Sunday, according to the Wall Street Journal, citing people familiar with the actions.

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The Teamsters, which represents about 22,000 unionized Yellow workers nationwide, announced Monday that the union received legal notice confirming Yellow's decisions, which general president Sean O’Brien called "unfortunate by not surprising."

"Yellow has historically proven that it could not manage itself despite billions of dollars in worker concessions and hundreds of millions in bailout funding from the federal government," O'Brien said in a statement. "This is a sad day for workers and the American freight industry."

USA TODAY could not immediately reach a representative from Yellow Corp. for comment.

Yellow bankruptcy had long loomed amid debt woes

The trucking company, whose 17.5 million annual shipments made it the third-largest in the U.S., had an outstanding debt of about $1.5 billion as of March and has continued to lose customers as its demise appeared imminent.

With customers leaving — as well as reports of Yellow stopping freight pickups last week — bankruptcy would “be the end of Yellow,” Satish Jindel, president of transportation and logistics firm SJ Consulting, told The Associated Press, noting increased risk for liquidation.

With bankruptcy looming, the company has been battling against the union for months.

Yellow sued the Teamsters in June after alleging it was “unjustifiably blocking” restructuring plans needed for the company’s survival, litigation the union called “baseless." O’Brien pointed to Yellow’s “decades of gross mismanagement,” which included exhausting a $700 million pandemic-era loan from the government, which the company has failed to repay in full.

'We gave and we gave'

The company is based in Nashville, Tennessee with employees spread among more than 300 terminals nationwide.

In Ohio's northeastern Summit County, hundreds of Yellow employees left jobless Monday expressed frustration to the Akron Beacon Journal, a USA TODAY Network publication. Many union workers told the Beacon-Journal that the company had failed to take advantage of wage and benefit concessions the Teamsters had made in order to keep the hauler out of a financial quagmire.

In the Summit County township of Copley, the company's terminal was blocked this week by trailers with a sign posted at the guard gate saying operations had ceased on Sunday.

"I thought I'd leave on my own terms, not theirs," Keith Stephensen, a Copley dock worker who said he started with Yellow 35 years ago in New York, told the Beacon-Journal. "We gave and we gave."

After efforts to help resolve Yellow's financial situation were unsuccessful, the Teamsters said Monday that it would shift focus to instead help its members find "good union jobs in freight and other industries."

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News of Yellow's collapse comes after the Teamsters last week secured an agreement to stave off another strike with UPS following months of negotiations, preventing a crippling blow to the nation's logistics network.

Following a bargaining process that began last August, the five-year agreement avoided what would have been the largest single employer strike in U.S. history.

Contributing: The Associated Press

Eric Lagatta covers breaking and trending news for USA TODAY. Reach him at [email protected].