Tributes are pouring in for Joe Strummer, leader of legendary '70s punk band The Clash, who died at his home in England Sunday. He was 50.

As reported by the BBC, U2's Bono said: "The Clash was the greatest rock band. They wrote the rule book for U2."

He termed Strummer's sudden death "such a shock."

Bob Geldof, speaking to BBC News 24, went on to say: "He was a clear contemporary, and we were rivals. I believed we had to get inside the pop culture -- he believed you should always stay outside and hurl things at it. We had endless arguments about it.

"As we all got older I realized what a nice person he was," Geldof added. "He was a very important musician. The Clash will be endlessly influential. They will always be one of the deathless rock bands. "

In a tribute published by the BBC, political singer-songwriter Billy Bragg wrote: "The ideals that still motivate me as an artist come not from punk, not even from the Clash, but from Joe Strummer."

Although it appears that Strummer -- whose real name was John Mellor -- fell victim to a heart attack, an autopsy is to be performed to confirm the cause of death.

Along with the Sex Pistols, The Clash helped re-establish London as an international music capital, especially as far as the punk scene was concerned. Strummer, who was born in Turkey to a British diplomat father, formed The Clash in the mid-'70s, and the band signed with CBS Records for $200,000.

Their first album, "Clash," was released in England in 1977. CBS considered the album too crude for U.S. release, however, and it wasn't until 1979 that a compilation album would be released as "The Clash" in America.

The band split in the early 1980s after a conflict between Strummer and others in The Clash, who subsequently formed the group Big Audio Dynamite (BAD).