U.S. federal authorities say Egyptian cleric Omar Abdel-Rahman has been hospitalized, and warns that his death could trigger possible terror attacks in the United States.
Rahman, known as the Blind Sheik, inspired extremists to carry out the 1993 attack on the World Trade Center. He is serving a life sentence in the United States.
In a bulletin, the Federal Bureau of Investigation says the 68-year-old was rushed to a hospital earlier this month.
Media reports quote law enforcement sources as saying there is no credible information that an attack is imminent.
The FBI bulletin includes a statement al-Qaida distributed in 1998, billed as Rahman's last will and testament, in which he called for "violent revenge" should he die in U.S. custody.
Rahman was sentenced in 1995 in New York to life in prison for inspiring the first World Trade Center attack and conspiracy to bomb targets in New York City.
Some information for this report provided by AP.