"Our friend and band-mate Ted has been feeling unwell for a few days, and yesterday he was taken to a hospital to receive emergency treatment," said the statement posted Tuesday.
"The scans revealed a blood clot on the surface of his brain that requires an operation. Ted is receiving excellent care and we are being assured that he will recover quickly from surgery."
The band said it is postponing its next three concerts, but will reschedule them "as soon as we can."
"We're all wishing Ted a speedy recovery," the statement said.