According to USA Today:

He's gone home. British guitar great Alvin Lee, who rose to global fame with a fiery performance at Woodstock, died Wednesday at age 68.

His website reports that Lee "passed away early this morning after unforeseen complications following a routine surgical procedure."

The statement from his family said, "We have lost a wonderful and much loved father and companion. The world has lost a truly great and gifted musician."

Lee's blues-rock band, Ten Years After, delivered a gripping 11-minute performance of I'm Going Homeat the 1969 Woodstock festival, an inarguable highlight even against marquee acts Jimi Hendrix and The Who. The song was on the band's second album, 1968's live Undead. But it was director Michael Wadleigh's 1970 Woodstock documentary, and its intense closeups of Lee's feverish vocals and guitar playing, that sparked the band's worldwide success.