CHICAGO (CBS) —  Thousands are all signed up for appointments at the soon-to-open United Center mass vaccination site.

Crews are putting the finishing touches on huge tents in the parking lot.

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Online and phone registration started Thursday for the 110,000 available slots. People over 65 get first priority.

People in Phase 1B Plus can sign up starting on Sunday at 4:00 p.m.

There will be a limited number of vaccines that will be distributed on March 9, but the full day of shots will begin on Wednesday March 10. The center will operate seven days a week for the next eight weeks.

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In a joint statement from the city of Chicago, Cook County, the state of Illinois and FEMA, as of 3:00 Thursday, 27,819 have signed up to receive the vaccine at the United Center.

People can sign up online through Zocdoc or they can call 312-746-4835.

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