SEATTLE -- Amazon has started to vaccinate thousands of its warehouse and delivery workers, contractors and their families in Washington state and plans to host more vaccination clinics to inoculate its employees.

Amazon.com Inc. hosted its first clinic on Monday, with employees receiving their first doses of the Pfizer COVID-19 vaccine.

Company spokesperson Karen Riley Sawyer said a second vaccination clinic is scheduled to open Tuesday at a Spokane warehouse, followed by additional vaccination opportunities at other company facilities across the state, The Seattle Times reported Monday.

鈥淎t first, I was hesitant to take the shot,鈥 said senior operations manager Alex Ivanov, who was vaccinated Monday.

Ivanov said he was nervous that the vaccine had been authorized for emergency use before receiving Food and Drug Administration approval, but changed his mind after watching his friends and family receive their shots.

鈥淭here's a lot of convenience, having it on site. If it wasn't on site, I probably wouldn't have done it,鈥 he said.

Amazon told Democratic Gov. Jay Inslee last year that the company would try to vaccinate its front-line workers as soon as they were eligible. The vaccination effort has served as a rebuke to critics who have claimed that the company did not take proper safety precautions during the pandemic.

While tens of thousands of Amazon corporate employees were allowed to work from home, about 1 million warehouse workers globally were required to report to their facilities as workloads soared because of increased demand for online shopping. The company also hired more than 400,000 people during the pandemic.

But some warehouse workers stopped showing up to work as concerns over the pandemic increased.

Amazon then rolled back its COVID-19 benefits, including pay increases and unlimited sick leave. The company has said its workers contracted the virus at rates comparable or lower than the national average.

Amazon has since implemented improved safety measures that were evident at the vaccination clinic on Monday, including signs asking people to social distance and plexiglass between employees checking temperatures.

It is not immediately know how many vaccination clinics Amazon will host for its employees.