Dennis Flemion, who co-founded the cult indie-pop act The Frogs with his younger brother Jimmy in Milwaukee in 1980 and rose to minor alt-rock celebrity in the ’90s, is missing and presumed dead in a Wisconsin lake, Matador Records co-owner Gerard Cosloy announced on the label’s blog tonight.

Beastie Boys co-founder Adam Yauch — known by his on-stage and behind-the-lens alter egos MCA and Nathanial Hörnblowér, respectively — lost a nearly 3-year-old battle with this morning, passing away in a New York hospital and leaving a deep musical and activist legacy that spanned the 1980s, ’90s and 2000s.

R.E.M. — the iconic college-rock band that soared to major-label uperstardom in the late ’80s and early ’90s before suffering the loss of a key original member — announced today that it has ‘decided to call it a day as a band’ after 31 years together.

British record producer Martin Rushent — who helmed The Human League’s genre-defining 1981 album ‘Dare,’ as well as beloved post-punk/New Wave-era records and singles by The Stranglers, Buzzcocks, XTC, The Go-Go’s and more — died Saturday. He was 63.

Punk icon Poly Styrene — who fronted the late-’70s group X-Ray Spex, still best known for its anthem ‘Oh Bondage Up Yours!’ — succumbed to cancer Monday night on the eve of her new record’s U.S. release. She was 53.

Mick Karn — who played bass in the acclaimed art-rock act Japan from the mid-’70s through the early ’80s and teamed up with Peter Murphy for the singer’s post-Bauhaus project Dalis Car — died today following a six-month battle with cancer. He was 52.

British industrial/experimental music pioneer Peter ‘Sleazy’ Christopherson — who co-founded the hugely influential acts Throbbing Gristle and Coil, was a member of Psychic TV and worked as an artist with famed album-cover design team Hipgnosis — died in his sleep on Wednesday at age 55.

German-born punk pioneer Ari Up — the frontwoman of The Slits who learned guitar from Joe Strummer and was John Lydon’s stepdaughter — died today at age 48 following ‘a serious illness,’ Lydon and her mother, Nora Foster, announced via Public Image Ltd.’s website.

Singer/bassist Michael Been of modern-rock trio The Call — best known for their ’80s radio hits ‘The Walls Came Down,’ ‘I Still Believe’ and ‘Let the Day Begin’ — suffered a heart attack and died tonight backstage at the Pukkelpop music festival in Belgium. He was 60.

News is spreading across the web this afternoon about the death of Malcolm McLaren, the legendary Sex Pistols manager/creator who famously claimed to have invented punk rock. To mark his death, we’ve posted the video for ‘Buffalo Gals,’ his highly influential hip-hop crossover single.

Simply awful news out of New Orleans tonight, as word emerges that Alex Chilton of the peerless power-pop act Big Star has died of an apparent heart attack just days before he was scheduled to perform with the reconstituted band at the South By Southwest music festival in Austin, Texas.

Larry Cassidy, co-founder and frontman of Factory Records postpunk outfit Section 25, has died, British music journalist John Robb reports today on his blog. The circumstances surrounding Cassidy’s death are not yet known.

Iain Burgess, a studio engineer renowned for his role in the ’80s Chicago punk underground and a major influence on and mentor to Steve Albini, died Thursday morning in France of a pulmonary embolism stemming from liver and pancreatic cancer, Albini’s Electrical Audio studios reports.