'We Are Family' - Joni Sledge of Sister Sledge dies at 60

• Video report by ITV News Correspondent Sejal Karia

"We Are Family" singer and Sister Sledge star Joni Sledge has died at the age of 60.

Sledge, who co-formed the group alongside her three sisters in 1971, was found unresponsive at her home in Phoenix, Arizona on Saturday.

Her cause of death is yet to be determined, according to a statement from the band's publicist.

Philadelphia-born Sledge fronted the pop group with siblings Debbie, Kim and Kathy and sang on 1979 disco anthem "We Are Family."

While the song went on to reach No. 2 on the Billboard Hot 100 and attain international fame, the band was also known for "He's the Greatest Dancer", "Lost in the Music" and a cover of Motown classic "My Guy".

In a Facebook statement released on Sister Sledge's page, the group described how numbness "fell upon our family" at the news of Joni's death.

"We are saddened to inform you that our dear sister, mother, aunt, niece and cousin, Joni passed away yesterday," the statement said.

It added: "We miss her and hurt for her presence, her radiance, and the sincerity with which she loved & embraced life."

Tributes for the singer included from Chic star Nile Rodgers, who helped write and produce the album "We Are Family".

On Twitter Rodgers wrote: "#RIPJoniSledge #WeAreFamily My heartfelt condolences to your family because they are my family too. We did something pretty amazing together."

La Toya Jackson also paid tribute to the singer, saying: "So sorry to hear that Joni Sledge has passed, my condolences to her family, friends and love ones. #Sistersledge we are family! #RIP".

Meanwhile TV star Ru Paul tweeted a screengrab of a Sister Sledge playlist with the short caption: "Sister Sledge Forever."

In November last year, Sister Sledge appeared on Peston on Sunday where they discussed the US presidential election.