ATHENS -- Greek singer Demis Roussos, whose often high-pitched pop serenades won him household recognition in the 1970s and 1980s across Europe and beyond and who sold more than 60 million records, has died in Athens at the age of 68, a hospital confirmed Monday.

The hospital said the singer died following a lengthy hospitalization, but did not give an exact cause of death.

For many an iconic presence with a colorful dress sense -- Roussos was once dubbed the Kaftan King -- and rotund, bearded appearance, he enjoyed the respect of his colleagues and a steady global following.

"He had a superb voice, he travelled in the world ... he loved what he was doing," singer Nana Mouskouri told French radio RTL in a tribute. "He was an artist, a friend. I hope he is in a better world."

Artemis (shortened to Demis) Roussos was born in June 1946 in Alexandria, Egypt, which had a large Greek community. His formative years in the ancient port city's cosmopolitan atmosphere were influenced by jazz, but also traditional Arab and Greek Orthodox music.

The family moved in the early 1960s to Greece, where Roussos took music lessons and played in amateur groups. He first came to prominence in the late 1960s with the band Aphrodite's Child, formed together with Vangelis Papathanassiou -- the Greek composer best known by his first name whose score for the film "Chariots of Fire" won him an Oscar in 1982.

His career launched, Roussos moved out of Greece to continue as a solo artist, recording hits such as "Forever and Ever," "My Friend The Wind," "Velvet Mornings," "Someday Somewhere," and "Lovely Lady Of Arcadia."

He listed Mozart and Sting among his favourite composers.

In 1985, Roussos was among 153 people taken hostage when two Shiite Muslim militiamen hijacked a TWA Boeing 727 on a flight from Athens to Rome, and he spent his 39th birthday on the plane. He was released unharmed five days later, and at a press conference thanked his captors for giving him a birthday cake.

Roussos enjoyed good food, which created problems with his weight that at one point reached 319 pounds. He managed to reduce that by a third in nine months and went on to co-write a book about losing weight.

He lived in Los Angeles, Paris, Monte Carlo, London and Athens.