George Martin, the record producer of the Beatles, died peacefully at his home at the age of 90, his manager said Wednesday. The cause of Martin’s death has not yet been released.

Martin, who was dubbed as the “fifth” Beatle, produced more than 700 records, and was behind 23 No. 1 singles for the English rock band in the U.S. and 30 in the U.K. The news of his death was first revealed by Beatles drummer Ringo Starr.

“God bless George Martin,” Starr wrote late Tuesday night. “Peace and love to Judy and his family, love Ringo and Barbara. George will be missed.” In another post, accompanied by a photo of Martin with the Beatles, Starr wrote: “Thank you for all your love and kindness.”

Martin’s manager, Adam Sharp of CA Management, later confirmed the death saying that Martin's family “would like to thank everyone for their thoughts, prayers and messages of support,” according to reports.

Martin was born on Jan. 3, 1926 in Highbury, London, at a carpenter's family. Over a career that spanned decades, Martin worked with several stars, including Peter Sellers, Shirley Bassey, America, Cheap Trick, Jeff Beck and Celine Dion.

Martin reportedly helped the Beatles achieve global success as the head of the Parlophone record label after hearing their demo tape in 1962.

“When I first met the Beatles in 1962, I didn't think much of their songs at all,” Martin told JazzWax.com in 2012. “But they learned so quickly how to write a hit. They were like plants in a hothouse. They grew incredibly fast.”

Martin also played on some Beatles songs, including the piano on “In My Life.”

“I couldn't play the piano at the speed it needed to be played, the way I'd written the part,” he said in another 2012 interview. “I wasn't that good a pianist, but if you had had a really good pianist, he could do it. I couldn't get all the notes in. One night I was by myself and played the notes at half speed but an octave lower on the piano, recording at 15 inches per second. When I ran the tape back at 30 inches per second, the notes were at the right speed and in the correct octave.”

Martin won multiple Grammy awards and an Academy Award for the sound score to "A Hard Day's Night." He received a knighthood in 1996 and in 1999, he was inducted into the Rock and Roll Hall of Fame.

British Prime Minister David Cameron expressed his sadness over Martin's death, calling him "a giant of music."

Here are some tweets from celebrities remembering the "fifth Beatle."