Ex-Beatle Paul McCartney will rock Mexico City's main plaza The Zocalo with a free concert that is expected to draw the largest number of people for a concert in the city's history, according to local authorities.

The free show in the heart of Mexico City, will celebrate "Dia de las Madres" (Mexican Mothers' Day) with an estimated attendance of at least 80,000 people. Restaurants and hotel reservations are sold out and fans were lining up since Monday to access the venue, according to reports from local newspapers.

About 4,500 policemen have been deployed to ensure the show goes on.

"Thanks to the Mayor and the people of Mexico for making this beautiful site available for our show. Also thanks to the sponsors and promoters who made this possible. We're really excited to play this one-off event - We're ready to rock!" McCartney wrote on his website ahead of the concert.

On Tuesday, McCartney performed before more than 70,000 people at the city's "Azteca Stadium" as part of the Mexico leg of his 2012 On the Run tour which included three dates.

McCartney's fans reportedly shouted nonstop throughout the concert, the first in nearly two years.

"Son a toda madre," McCartney reportedly shouted at his fans meaning "You rock."

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Tags: Paul McCartney