Helmut Kollen, the former bassist and singer for the German progressive rock group Triumvirat died of carbon monoxide poisoning in his garage at the age of 27. He was listening to tracks from the album he was working on while in his car with the engine running.

Kollen joined Triumvirat, considered to be Germany's equivalent of Emerson, Lake and Palmer, in 1974. He was on their two most successful albums, Illusions on a Double Dimple and Spartacus, which reached No. 27 on the Billboard Top 200 before leaving for a solo career in 1975. In Oct. 1977, his solo album was released under the title You Won't See Me.

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