Celebrities React To Whitney Houston Death: Mariah Carey, Katy Perry, Simon Cowell, More

The world has reacted with shock to the news that Whitney Houston has died, aged 48.

The singer's publicist confirmed her tragic passing earlier this evening.

The idol has a movie coming out this summer - 'Sparkle' alongside Jordin Sparks - and was TODAY linked to The X Factor USA.

Stars including Toni Braxton and Mariah Carey have been paying their respects online.

Toni Braxton, singer: "She's paved the way for every single singer in the music industry. Iconic, legendary, innovating, amazing, humble...1 the best in the world"

Mariah Carey, singer: "Heartbroken and in tears over the shocking death of my friend, the incomparable Ms. Whitney Houston... She will never be forgotten as one of the greatest voices to ever grace the earth."

LA Reid, record label manager: I am completely devastated by the loss of the greatest voice of all time! R.I.P. Whitney Houston. I will always love you!

Katy Perry, singer: "So devastating. We will always love you Whitney, R.I.P."

Rihanna, singer: "No words! Just tears #DearWhitney"

Simon Cowell, music mogul: "I am so sad to hear about Whitney. We have lost one of the greatest singers of all time."

Christina Aguilera, singer: "We have lost another legend. Love and prayers to Whitney's family. She will be missed."

Joan Rivers, comedian: "Whitney Houston. What a sad tragedy-the end of the life of an incredible talent. RIP to an amazing singer and legend."

Justin Bieber, singer: "just heard the news. so crazy. One of the GREATEST VOICES EVER just passed. RIP Whitney Houston. My prayers go out to her friends and family"

Vanessa Williams, actress and singer: "Condolences to #whitneyhouston's family. What a tragic loss for the music world and her fans around the globe :("

Cheryl Cole, singer: "So sad :-( .."

Olly Murs, singer: "Jeez....is it true Whitney Houston is dead?!? If so #RIPwhitneyhouston what a sensational talent!! One of the best singers ever!!"

Christina Perri, singer: "oh whitney. my heart just broke. i hope you rest your beautiful soul."

Paris Hilton, socialite: "So sad to hear the news about Whitney Houston. :( She was such a beautiful and talented woman. My heart goes out to her family. RIP"

Rebecca Ferguson, singer: "I wanted to meet her and tell her she's the reason why I wanted to sing when I was little devastated!"

Nicola Roberts, Girls Aloud singer: "No no no no no... I can't believe it I'm devastated"

Melanie Amaro, X Factor USA winner: "I refuse to believe that I JUST met one of my two idols for the first time and 3 days later she is dead !!! Lies !!!! I won't believe :'("

Kevin McHale, Glee actor: "it's incredible the impact one voice can have. Whitney, you changed so much. A true Icon."

Lea Michele, Glee actress: "I'm speechless. Such sad news about Whitney Houston.."

Amber Riley, Glee actress: "I had to pull over off the road. RIP Whitney Houston. I'm glad now that I got to meet you and thank you for your beautiful music."

Demi Lovato, singer: "This can't be true... One of my idols gone?? No. This is so unbelievably sad... #RIPWhitneyHouston"

Randy Jackson, music mogul: "wow I am devastated. the world has lost another one of the best voices in history. RIP whitney houston, so fortunate am I to have worked with u, and have u touch my life. may god bless this family."