A shipment of 650-thousand doses of Pfizer's COVID-19 vaccine, enough to inoculate 325-thousand people, arrived in South Korea on Wednesday. 

According to the state vaccine task force, the shipment, which is part of some 66 million doses that South Korea purchased directly from the U.S. pharmaceutical company, landed at Incheon International Airport at 1:35 a.m.

South Korea was set to receive seven million doses from Pfizer by the end of the first half of this year, which has now been completed with the latest batch. 

The two-dose Pfizer vaccines are being earmarked for seniors aged 75 and older, as well as those under 30 who are excluded from the AstraZeneca vaccine due to its link to rare blood clots, including soldiers and essential social workers.

The country with a population of 52 million has so far secured five types of vaccines for nearly 100 million people.