Paul Kantner of Jefferson Airplane Is Dead at 74

The rocker founded Jefferson Airplane and its spin-off, Jefferson Starship.

Longtime Jefferson Starship publicist Cynthia Bowman told the San Francisco Gate that the cause of death was multiple organ failure. Kantner had suffered a heart attack this week, according to the newspaper.

Kantner formed Jefferson Airplane in 1965 with his friend, singer Marty Balin, and the band's initial lineup also included singer Signe Anderson, guitarist Jorma Kaukonen, bassist Jack Casady and drummer Skip Spence. After releasing its debut album, "Jefferson Airplane Takes Off," in 1965, singer Grace Slick was brought in to replace Anderson and Spencer Dryden took over for Spence. This lineup of the group went on to record the group's landmark 1967 record, "Surrealistic Pillow," which featured the band's only top 10 hits -- "Somebody to Love" and "White Rabbit."

After Jefferson Airplane broke up in 1972, Kantner formed a new group with Slick called the Jefferson Starship, which Balin eventually joined. That group released a series of pop and rock hits throughout the 1970s and into the '80s. Kantner exited the band in the mid-80s over the artistic direction of the group, and then formed the short-lived KBC Band with Balin and Casady.

In March of 2015, Kantner suffered a heart attack, but he returned to Jefferson Starship after a period of recovery and continued to perform with the band until his death.

He is survived by his daughter and two sons.