Michael Hayden, the former head of the CIA and the National Security Agency who is recovering from a stroke he suffered last month, sent out a tweet wishing his supporters a merry Christmas.

"Many thanks for all the prayers and good wishes," he wrote. "It's humbling and overwhelming. Had [Monday] evening and [Christmas] off. Spent good time with my family. [Wednesday] it is back to the hard work of therapy."

Last month his family sent out a statement announcing the retired U.S. Air Force four-star general had been hospitalized after suffering a stroke at home, The Washington Times reported.

The family added in its statement: "He is receiving expert medical care for which the family is grateful. As Gen. Hayden begins the healing process, the family requests that their privacy be respected."

Hayden, 73, served as director of the NSA from 1999 to 2005 and then headed the CIA under former President George W. Bush before retiring in 2009 at the beginning of the Obama administration.

At the time of his stroke, he was serving as a CNN national security analyst and as a visiting professor at George Mason University in Virginia.

Hayden is an outspoken critic of President Donald Trump and was one of more than a dozen former intelligence officials who signed a statement denouncing the president's decision to take away fellow former CIA boss John Brennan's security clearance this past August.

Earlier this year, Hayden published a book called "The Assault on Intelligence: American National Security in an Age of Lies."

• Former CIA Chief Michael Hayden Hospitalized After Stroke
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