Amazon has rewarded eight employees with prizes following a draw from its Max Your Vax corporate lottery, the company announced.

It gave away cars and $100,000 cash bonuses to a handful of vaccinated warehouse workers as part of sweepstakes it’s running to encourage employees to get inoculated, according to CNBC.

Four warehouse workers and a Whole Foods employee were awarded cars worth up to $40,000 after they provided proof they had received the COVID-19 vaccination, Amazon revealed.

Last month the company introduced the lottery to offer cash prizes of as much as $500,000 and vacation packages in addition to the cars to frontline employees proving they have had jabs.

A total of 18 prizes worth nearly $2 million will be awarded through to October 21, according to Amazon.

Amazon said it believes getting vaccinated is critical for employees to protect themselves and communities. Amazon has held more than 1,500 on-site vaccination events for employees and their families, the company added, CNBC reported.

Amazon hasn’t required its front-line workers to get vaccinated, but these sweepstakes serve as a nudge to encourage vaccination.

It is eager for its hundreds of thousands of frontline workers to get vaccinated as the COVID-19 delta variant spreads rapidly across the globe. The company has resumed some coronavirus safety measures that were previously in place, including face mask mandates in US warehouses, according to CNBC.

In an email to Bloomberg in August, Amazon spokesperson Kelly Nantel said that the company “strongly believe that the best way to protect our front-line employees and communities from COVID-19 is through vaccinations, and we are proud to have hosted more than 1,100 on-site vaccination events to help make getting a vaccination as easy as possible for our employees and their household members.