Apple CEO Steve Jobs is taking a medical leave of absence from the company. Jobs revealed the leave in a letter to employees today, saying "during the past week I have learned that my health-related issues are more complex than I originally thought."
Jobs wrote that he expects the leave to last until at least the end of June, during which time COO Tim Cook will take the reigns.
Trading was halted in extended trading after the announcement, which came after the market closed.
A survivor of pancreatic cancer, Jobs' health has been a point of rampant speculation for several months, after he appeared at recent events looking thinner than normal.
Last week, he issued a public notice saying he had a hormonal imbalance that was being treated which caused his gaunt appearance, and he skipped his annual MacWorld keynote for the first time since returning to the company.