Ahmad Khan Rahami, key suspect in the bombings that shook lower Manhattan Saturday night, left behind a “rambling” note citing deceased al-Qaeda leader, Anwar al-Awlaki.

According to NBC News, the letter also mentioned other terrorist attacks like the Boston bombing.

From NBC News:

Bombing suspect Ahmad Khan Rahami left behind a “rambling” note mentioning a slain al-Qaeda leader, NBC News learned Tuesday.

It was “a hodgepodge, a rambling, disconnected, choppy series of references to past events,” a law enforcement official said.

The note referenced the deadly Fort Hood shooting and the Boston Marathon bombings as well as slain Al Qaeda terrorist Anwar al-Awlaki, the official said.

NBC News has not yet confirmed details on when or where the note was found.

The revelation that Rahami left a note came Tuesday, a day after the search for the 28-year-old suspect ended with a gun battle in Linden, New Jersey. The suspect and two police officers were wounded in the shoot-out.

Like terrorist attacks prior to this one, individuals close to the suspect contacted authorities years ago, alerting them Rahami might be into terroristy things. In this case, it was Rahami’s father.

The New York Times reports:

Two years before the bombings that Ahmad Khan Rahami is suspected of carrying out in New York and New Jersey, his father told the police that his son was a terrorist, prompting a review by federal agents, according to two law enforcement officials.

The father, Mohammad Rahami, in a brief interview on Tuesday, said that at the time he told agents from the Federal Bureau of Investigation about his concern, his son had just had a fight with another of his sons and stabbed the man, leading to a criminal investigation.

“Two years ago I go to the F.B.I. because my son was doing really bad, O.K.?” he said. “But they check almost two months, they say, ‘He’s O.K., he’s clean, he’s not a terrorist.’ I say O.K.”

He added: “Now they say he is a terrorist. I say O.K.”

It is not clear if officers ever interviewed Ahmad Rahami, but as investigators turn their focus to what might have motivated, inspired or led him to plant bombs in Chelsea in Manhattan and on the Jersey Shore, new clues are emerging indicating that he may have been increasingly receptive to extremist ideology.

Despite knee-jerk claims that Rahami is yet another “lone wolf” who was at some point mysteriously radicalized into committing crimes that don’t speak for the whole of Islam, five other individuals were detained in relation to the Chelsea bombing.

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