Attorneys for the man at the center of a 2002 killing spree in the nation’s capital released a letter from their client Wednesday proclaiming his innocence.

In the incohesive, barely coherent letter, John Allen Muhammad, who is scheduled to die by lethal injection on Nov. 10, writes that “exculpatory evidence” withheld from his trial "will prove my innocent and what really happen ....[sic]"

The 48-year-old sniper was deemed a father figure for his teenage accomplice, Lee Boyd Malvo, who is serving a life sentence. The letter, dated May 2008, was filed in federal court in connection with Muhammad's unsuccessful attempt to block his execution, according to his attorneys, The Associated Press reports.

Chock full of misspellings and grammatical errors, the letter says: "So all you police and prosecutors can stand-down-'rushing' to murder this innocent Black man for something he nor his son (Lee) had nothing to do with ...." Lee Boyd Malvo is of no relation to Muhammad.

Muhammad was convicted of killing Dean Harold Meyers at a Manassas, Va., gas station during a three-week spree that killed 10 in October 2002. The killings happened in Maryland, Virginia and the District of Columbia.

Tuesday, Muhammad's attorneys asked the U.S. Supreme Court to stop his execution.

Muhammad's lawyers also have asked Virginia Gov. Timothy M. Kaine for clemency, saying Muhammad is mentally ill and should not be executed.