Vaccinations for the South Korean police, coast guard and fire officials will begin next week.

According to the nation's vaccine authorities on Monday, some 507-thousand members of the national police force, coast guard and fire agency will begin receiving the vaccine by AstraZeneca and Oxford University next Monday.

Those under the age of 30, however, will be excluded due to concerns over rare cases of blood clots.

Amid a global vaccine shortage and safety concerns, authorities have adjusted the vaccination program for the second quarter. Emergency personnel were previously scheduled to start receiving vaccines in June.

Meanwhile, the doses that were initially set aside for those under 30, enough for 640-thousand people, will be used to immunize those aged 60 to 64 starting as early as mid-May, as opposed to the third quarter.

Additional AstraZeneca vaccines, enough to cover three-point-five million people, are confirmed to arrive in South Korea between May and June.