CHICAGO — The mayor of Joliet said Friday that he has asked the governor to launch an investigation into the coronavirus-related deaths of 23 residents and a staff member at a nursing home in the northern Illinois city.

A spokeswoman for the facility, Symphony of Joliet, announced the deaths on Wednesday. The facility had reported a total of three deaths as recently as last week.

Joliet Mayor Bob O’Dekirk said that he had asked Gov. J.B. Pritzker’s office late Thursday to initiate an investigation by the Illinois Department of Public Health and to “start untangling the mess of what happened inside that nursing home.”

“We don’t have the answers right now, but we’re going to get the answers,” he said. “Certainly Joliet families (and) people who lost their loved ones inside the nursing home have a right to get those answers.”

Spokeswomen for the governor’s office and nursing home, and officials from the health department didn’t immediately reply to Friday emails seeking comment about the mayor’s request.

Nursing homes in the U.S. and other countries have struggled to control outbreaks among their residents, whose age and existing medical conditions make them more vulnerable to serious illness and death as a result of becoming infected.

The Associated Press found this week that at least 3,621 deaths nationwide have been linked to nursing homes based on media reports and information provided by state health departments. The federal government has not kept a national count and public reports likely underestimate deaths due to lack of testing.

The Chicago Tribune reported Friday that nearly 300 residents and staff at Illinois nursing homes had died from COVID-19, the disease caused by the coronavirus, but state health officials have not named specific facilities.

As of Thursday, 1,072 people had died of COVID-19 and 25,733 had tested positive for the disease. For most people, the coronavirus causes mild or moderate symptoms, such as fever and cough that clear up in two to three weeks. For some, especially older adults and people with existing health problems, it can cause more severe illness, including pneumonia.