'Fifth Beatle' George Martin dies aged 90

George Martin, known as "the fifth Beatle" for his work in shaping the band that became one of the world's most influential music forces, has died at the age of 90.

He was considered the most successful music producer in history, cited in the Guinness Book of Records for having more than 50 No 1 hit records over five decades in the United States and the United Kingdom alone.

"God bless George Martin peace and love to Judy and his family. ... George will be missed," Ringo Starr, the Beatles' drummer, said on Twitter.