LOS ANGELES — Guild members of the Los Angeles Times walked off the job Friday to protest what it says are imminent layoffs, the first newsroom union work stoppage in the newspaper’s 143-year history.

The paper’s journalists and their supporters rallied in an LA civic center park, chanting and waving signs that read, “Don’t Cut Our Future.” The guild said members would also protest in other cities.

The guild said in a statement that the Times is planning to lay off a “significant” number of journalists, but that the union cannot specify the number because management has insisted on negotiating in meetings that are off the record. The guild also said the paper wants to gut seniority protections.

Dr. Patrick Soon-Shiong, a biotech billionaire, acquired the Times in 2018, returning it to local ownership two decades after it was sold to Tribune Co. The purchase raised hopes after years of cutbacks, circulation declines and leadership changes.

Last week, Executive Editor Kevin Merida abruptly left after a 2 1/2-year tenure. In June, more than 70 positions — about 13% of the newsroom — were cut.

A Times’ representative told the paper that revenue projections were under review and expenses were being carefully examined.

“We need to reduce our operating budget going into this year and anticipate layoffs,” spokeswoman Hillary Manning said in a statement.