Nine in 10 New York City municipal workers received COVID-19 vaccinations as a Monday deadline loomed under a city mandate, according to Mayor Bill de Blasio.

De Blasio tweeted Saturday night that 91% of city workers had received the vaccine, which represented a jump from about 83% as of Friday night.

Under a city mandate, those who haven’t received at least one dose of the vaccine will be put on unpaid leave starting Monday, raising the possibility of shortages of police, fire and EMS workers. New York has more than 300,000 employees.

The police department, which employs about 36,000 officers and 19,000 civilian employees, reported an 84% vaccination rate as of Sunday morning, while roughly two in 10 of the fire department’s roughly 17,000 employees remained unvaccinated as of Friday night. Updated fire department figures were expected later Sunday.

Fire Commissioner Daniel Nigro denied reports that some firehouses had been closed due to shortages.

“The department has not closed any firehouses,” Nigro said in a statement Sunday. “Irresponsible bogus sick leave by some of our members is creating a danger for New Yorkers and their fellow firefighters. They need to return to work or risk the consequences of their actions.”

City officials have considered various measures to deal with an expected staffing shortfall Monday.

The fire department has said it was prepared to close up to 20% of its fire companies and have 20% fewer ambulances in service while also changing schedules, canceling vacations and turning to outside EMS providers to make up for expected staffing shortages.

De Blasio said the sanitation department will move to 12-hour shifts, as opposed to the usual 8-hour shifts, and begin working Sundays to ensure trash doesn’t pile up.

(AP)