Aficionados poured in from as far afield as Peru and Tokyo for a weekend of live music and Beatlemania, which kicked off with 1,631 people singing "Love Me Do" outside the city's central Liver Building.

Local choirs, school groups and lunching office workers joined in, breaking the previous record for singing "in the round" - where two groups sing exactly the same melody, beginning at different times - to break the previous record of 897, according to Guinness World Records.

"The demographics here today are interesting - it goes from people in their 70s to school kids," said Dave Jones, who runs Liverpool's famous Cavern Club where the Beatles were the house band between 1961 and 1963 and which is staging a weekend-long extravaganza of their music.

"We're trying to recreate the atmosphere of those glory days in the 60s," Jones told Reuters. "It's generation after generation enjoying the music."

The 50th birthday of Love Me Do is also the anniversary of a lucky break for the band.

Beatles producer George Martin told the BBC the song was the "best of a bad bunch". The broadcaster plans to air a documentary this weekend containing claims that the band's manager bought thousands of copies to help the record get to number 17 in the UK charts.

Auction house Sotheby's is marking the anniversary by selling the original collage used for the insert of the 1967 Beatles album Sgt. Pepper's Lonely Hearts Club Band. Sotheby's expects it to sell for 50,000-80,000 pounds ($81,000-$129,500).

(Additional reporting by Mike Collett-White, editing by Paul Casciato)

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