Late Thursday night, rocker Bret Michaels was rushed to an undisclosed hospital, where doctors discovered he had suffered a massive brain hemorrhage, according to People magazine. A rep for the singer confirmed to MTV News that the report is accurate and said they will not have further information until more testing is done.

At press time, Michaels, 47, was reportedly in critical condition. A source told People that he was first taken to the hospital after complaining of "an excruciating headache," and upon examination, doctors learned he had suffered a subarachnoid hemorrhage, or bleeding at the base of his brain stem.

"After several CAT scans, MRIs and an angiogram, [doctors] decided to keep Michaels in the ICU and are running several tests to determine the cause [of the hemorrhage]," the source told People. "[It] will be touch and go for the next few days while he is under intense observation."

Earlier this month, Michaels — who is also diabetic — was admitted to a hospital in San Antonio with what he believed was a stomach flu, but doctors diagnosed him with acute appendicitis and rushed him into emergency surgery. Following the procedure, his spokesperson said Michaels was "doing well and beginning the recovery process."

Michaels remained in the hospital under his doctor's care and then was transferred to a rehabilitation facility that specializes in diabetic patients. While in recovery, he wrote a note to his fans thanking them for their support and expressed his desire to return to the current season of NBC's "Celebrity Apprentice," which he is still in the running to win.

A statement posted Wednesday on Michaels' website once again thanked fans for their well wishes and said that he was rescheduling the shows he was forced to cancel after undergoing the appendectomy.