"Bummer. Just spent the day discussing touring up through next summer, then play our asses off to the least responsive audience I can ever remember playing to," band leader Trent Reznor said in a message posted at NIN's website. "I know I'm bitching but it's a sh--ty feeling. As I'm walking to the bus to leave Sacramento as soon as I can, I learn Jerome is back in the hospital. I have no idea what this means."

"Dillon is returning to Los Angeles immediately to undergo tests for problems related to a heart condition discovered earlier this month while on tour," reads a press release issued Thursday (9/29).

On Sept. 16, Nine Inch Nails cut short its tour opener in San Diego when Dillon reportedly was unable to continue playing. Initial reports claimed that the drummer had been suffering "chest pains," but Dillon refuted those claims in a Sept. 20 message he posted in the forum at his official website.

"Not exactly the way I wanted to start the arena tour," Dillon wrote. "Fatigue and exhaustion are to blame for what happened with me the other night. Incidentally, I did not experience 'chest pains'--but I did spend the night at the hospital for observation. I received a clean bill of health the next morning and could not get back on the bus fast enough."

Dillon's condition has resulted in the postponement of NIN's Friday (9/30) show in Oakland, CA, which will now take place Nov. 19. Tickets for the original performance will be honored on the make-up date, according to organizers. Ticketholders seeking a refund instead are asked to return their tickets to the place of purchase by Oct. 7.

Nine Inch Nails are in the midst of an arena tour that backs their latest album, "With Teeth." The set, which is the group's first since 1999's "The Fragile," debuted at No. 1 on The Billboard 200 chart.