Soul legend Edwin Starr has died at the age of 61, and is thought to have had a heart attack.
The singer was best-known for his lasting hit single War
The US-born star had been making records since the 1950s and was best-known for his enduring hits War and Contact.
Starr, who was one of the first artists to be signed to the Motown record label, died at his home near Nottingham, his manager Lilian Kyle said.
He had lived for many years in the UK.
The 1970s rock star Suzi Quatro, who has known Starr since she was a teenager in Detroit, led tributes to the singer.
She said: "He was the best. There was nobody better on stage and he was the nicest man you could ever wish to meet."
Starr had been due to play the Womad festival in Reading in July.
Starr, who was born Charles Hatcher, began his music career in The Future Tones in 1957.
But after just one single he was drafted into the Army for three years.
Following his military service he went on a two-year tour before signing his first solo deal in 1965.
His music was picked up by DJs in soul and dance clubs in the UK, helping make hits of Agent Double O-Soul and Stop Her On Sight (SOS).
His biggest hit was the protest song War, which asked "what is it good for?", in 1970.
The track was later covered by UK band Frankie Goes to Hollywood.
Top 10 hits followed in the late 70s with disco numbers Contact and H.A.P.P.Y Radio.
And he continued to perform live shows, and was a favourite on the soul festival circuit.
Starr performed at the wedding of Liza Minnelli
He performed two shows in Stuttgart, Germany, at the weekend to an audience of more than 16,000 people.
Starr was one of the guest performers at the lavish celebrity wedding of Liza Minnelli and David Gest last year, and has also sung live with Bruce Springsteen.
Away from singing he also presented a BBC Radio 2 series about the civil rights movement, which was nominated for a prestigious Sony Award.
Close friend Paul Carvell said: "His death has come as a total shock.
"His health hasn't been brilliant recently but he kept that away from most people and continued to give it his all when he performed.
"There is one more star in heaven tonight," he added.