Dolores O'Riordan, lead singer of Irish band The Cranberries, has died at 46. The Limerick band became well-known internationally in the 1990s with hits including "Zombie" and "Linger."

Publicist Lindsey Holmes says O'Riordan died suddenly Monday in London, where she was recording. The cause of death wasn't immediately available.

Holmes says the singer's family is "devastated" by the news.

O'Riordan was still active in her career, performing as recently as December, according to The Cranberries' social media accounts. In November, she recorded the theme song for a short film called "Angela's Christmas," which aired on Irish TV in December. 

Last year, The Cranberries announced on social media that O'Riordan was having a tough recovery from an ongoing back problem, forcing the band to cancel  most of its European tour. However, in December, the singer tweeted, "Feeling good! I did my first bit of gigging in months at the weekend, performed a few songs at the Billboard annual staff holiday party in New York with the house band. Really enjoyed it!"

Musicians and fans mourned O'Riordan on Twitter. 

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