CHICAGO (CBS) — Tonight’s Mega Millions drawing has swelled to a $1 billion jackpot, and the Illinois Lottery is celebrating by giving away 1,000 free tickets.

The #1 billion million jackpot is the second largest lottery prize in U.S. history, behind only a $1.6 billion Powerball jackpot in 2016.

To celebrate, the Illinois Lottery is giving away 1,000 tickets at the Thompson Center. The event originally started as a giveaway of 970 tickets, to match the $970 million prize total at the start of the day, but when the jackpot swelled to $1 billion later Friday morning, Lottery officials also upped the number of free tickets.

People lined up around the block for a chance to enter a prize booth, where they would try to grab as many tickets as possible in five seconds once a wind machine inside started blowing tickets around.

The giveaway will continue until about 1 p.m.

The drawing for the $1 billion jackpot will be at 10 p.m. Winners can chose how to be paid; either in 29 annual installments, or a one-time lump sum payment. For the $1 billion jackpot, the lump sum payment would be $565 million before taxes.