WASHINGTON — U.S. employers advertised slightly more job openings in October, but hiring slipped as a resurgence of COVID-19 threatens the economic recovery. And the number of Americans fired or laid off rose for the first time since June.

Job postings rose to 6.65 million in October from 6.49 million in September, the Labor Department reported Wednesday. But employers hired 5.81 million workers, which is less than the 5.89 million hires in September.

In its Job Openings and Labor Turnover Summary (JOLTS), the Labor Department reported that companies and government agencies laid off or fired 1.68 million workers, up from 1.44 million in September. Federal government layoffs of temporary Census workers contributed to the uptick.

The American job market has been slowly healing since it collapsed in the spring when the coronavirus pandemic struck the United States hard. Employers slashed 22 million jobs in March and April, then began recalling furloughed employees back to work.

But the job rebound has been slowing and is threatened by a rebound in COVID-19 cases.

The Labor Department reported Friday that employers added 245,000 jobs last month, marking a sharp and steady deceleration from 4.8 million new jobs in June, 1.8 million in July, 1.5 million in August, 711,000 in September and 610,000 in October.

In all, the American economy is still 9.8 million short of the jobs it had in February.