Credit Junfu Han / Detroit Free Press Three semi-trucks loaded with the nation's first doses of a COVID-19 vaccine rolled out of the parking lot of the Pfizer manufacturing plant early Sunday morning, met with cheering crowds of local residents who said they were proud of their hometown's contribution to science, and helping to bring the end to the coronavirus pandemic. The caravan of FedEx, UPS and Boyle Transportation trucks — led and tailed by unmarked police cars — pulled out of the parking lot about 8:25 a.m., headed to airports and distribution centers on a historic journey. Millions of doses of the company's coronavirus vaccine were inside those trucks, and could be injected into the arms of the American people as early as Monday morning.