New York City Mayor Bill de Blasio said Saturday that 9 in 10 municipal workers received COVID-19 vaccinations as today’s deadline loomed under a city mandate, according to ABC News.

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

According to a city mandate, people who have not received at least one dose of the vaccine will be put on unpaid leave starting today, raising the possibility of shortages of police, fire, and EMS workers. Currently, the city has more than 300,000 employees.

As of Sunday morning, the police department, which has about 36,000 officers and 19,000 civilian employees, reported an 84% vaccination rate, and the fire department said that 80% of its employees were vaccinated.

Fire Commissioner Daniel Nigro said Sunday morning that firehouses had not been closed due to shortages.

He said, “The department has not closed any firehouses. 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.”

Meanwhile, city officials are considering various measures to deal with an expected staffing shortfall.

“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,” according to ABC News.

De Blasio said the sanitation department will move to 12-hour shifts and begin working Sundays to ensure trash does not pile up.

The story originally appeared on ABC News.