At a hastily called news conference on Saturday, elected officials in Costa Mesa, a city of 113,000 people about 40 miles south of Los Angeles, expressed opposition to a state plan to send dozens of patients to the Fairview Developmental Center, a nearly vacant state hospital formerly used for people with developmental disabilities.

“We’re a compassionate community,” said the city’s mayor, Katrina Foley. “But we are not going to continue to be the place where everybody drops off their crises and expects us to correct it.”

The patients involved would be people now quarantined at Travis Air Force Base who have tested positive for the coronavirus but do not have severe symptoms requiring hospital care. Several people confirmed to have the virus are quarantined in their homes across the United States, but that is not an option for some, including people who do not live alone; the authorities are trying to find a secure place for them to stay. Wherever they go, they would be kept away from contact with the public until the danger of contagion passes.

Local officials in Costa Mesa were told of the plan on Thursday night, and filed a request for an emergency injunction in federal court on Friday.