Il Divo singer Carlos Marin has died aged 53, the group has announced.
A statement on Twitter said: "It is with heavy hearts that we are letting you know that our friend and partner, Carlos Marin, has passed away.
"He will be missed by his friends, family and fans. There wiIl never be another voice or spirit like Carlos.
"For 17 years the four of us have been on this incredible journey of Il Divo together, and we will miss our dear friend.
"We hope and pray that his beautiful soul will rest in peace. With Love — David, Sebastien and Urs."
Marin was reportedly rushed into hospital in Manchester in recent days and was thought to be in an intensive care unit, though his cause of death or the nature of his illness has not yet been revealed.
The group had already postponed the rest of their tour dates in the hope that Marin would make a recovery.
Il Divo was a conceived by Simon Cowell in 2003, and signed to his label Syco, going on to release 10 studio albums and shifting 30 million records.
In his personal life, the baritone was married to Geraldine Larrosa, whom he tied the knot with in Disneyland in California in 2006, before divorcing her in 2009.
Away from Il Divo, he performed in a number of musicals including Les Miserables, Grease and Beauty And The Beast.