An additional 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 batch, 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.

The latest round brings the total amount of vaccines received from Pfizer so far to six-point-35 million doses. South Korea is scheduled to receive seven million doses by the end of the first half of this year. 

The lion's share of the Pfizer vaccines are currently 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 52 million population has so far secured vaccines for nearly 100 million people.