Earth, Wind & Fire drummer John Paris is the band member who suffered a medical emergency that forced the group to postpone its San Francisco concert, sources familiar with the situation tell TMZ.
None of the group's three longtime members—Philip Bailey, Verdine White, and Ralph Johnson—were involved.
The San Francisco Fire Department responded to the venue for a cardiac incident.
A fire engine and a private ambulance were dispatched, and one person was transported to a local hospital in critical condition.
Paris' current condition is unclear.
Earth, Wind & Fire postponed its Thursday night show with Lionel Richie at San Francisco's Chase Center after a band member suffered a medical emergency.
The concert was called off shortly before the performers were set to take the stage.
Reps for Earth, Wind & Fire have not yet responded to requests for comment.
