About 1,440 workers at four U.S.-based Kellogg cereal plants went on strike Tuesday, grinding the company's production to a halt, The Associated Press reported.

Daniel Osborn, a union president at Kellogg’s plant at Omaha, Neb., told the newswire that the workers union and the Kellogg Company have been in talks about a bargaining deal for more than a year. 

The union’s dispute involves an assortment of pay and benefits issues, including the loss of premium health care, holiday pay and reduced vacation time, according to the AP. 

Osborn also mentioned the Battle Creek, Mich.-based company threatened to move some jobs to Mexico. 

“A lot of Americans probably don’t have too much issue with the Nike or Under Armor hats being made elsewhere or even our vehicles, but when they start manufacturing our food down where they are out of the FDA control and OSHA control, I have a huge problem with that,” Osborn told the AP. 

Osborn also said that operations still resumed during the pandemic, with workers clocking in 12-hour shifts seven days a week to keep up production as other employees were out sick with COVID-19, the AP reported. 

“The level we were working at is unsustainable,” Osborn said.

Kellogg, for its part, stated it offered workers increased wages and benefits and added that on average its employees earned a yearly salary of $120,000 in 2020. 

Kellogg spokesperson Kria Bahner said in a statement that the company is disappointed with the union strike, citing that the company provides compensation and benefits "that are among the industry's best."

Osborn said that he expects Kellogg to bring in nonunion workers in an attempt to resume operations and maintain supplies of its products, the AP noted.

The Hill has reached out to Kellogg for comment.