Grateful Dead co-founder Bob Weir has died at 78.

Bob Weir, co-founder and rhythm guitarist of the Grateful Dead, has died at 78, a statement on his verified Instagram said; he was diagnosed with cancer in July and 'succumbed to underlying lung issues' while surrounded by loved ones.

Veteran rock musician Bob Weir, a co-founder and the Grateful Dead's rhythm guitarist, has died at age 78, according to a statement posted to his verified Instagram. The statement said he was diagnosed with cancer in July and "succumbed to underlying lung issues" while surrounded by loved ones. The statement did not specify when or where he died. Key facts: - The death was announced in a statement on Weir's verified Instagram account. - The statement reported a July cancer diagnosis and that he "succumbed to underlying lung issues" while surrounded by loved ones. - The statement did not name the time or place of death. - Weir co-founded the Grateful Dead, served as the band's rhythm guitarist and a main vocalist, and wrote songs including "Sugar Magnolia", "Playing in the Band" and "Jack Straw". Summary: Weir's passing follows the July cancer diagnosis reported in the Instagram statement and closes a long public musical career that included solo work with RatDog and reunions with surviving Grateful Dead members. Undetermined at this time.