On Thursday, an emotional Roger Goodell gave his first interview since a gunman killed four people Monday in a targeted attack on the NFL's Manhattan office.

Goodell spoke remotely by video to NBC's Mike Tirico from New York. The 66-year-old, who opted not to attend the NFL's Hall of Fame Game in Canton, Ohio, instead attended the funeral of slain NYPD officer Didarul Islam.

Goodell outlined feeling a sense of "tremendous loss" at the funeral, despite noting it was a "heartwarming service."

"[He's] somebody that we see outside the building most every day when we come in," Goodell said of Islam. "And it hits home, the unnecessary and unexplainable loss. It's something that all of us as New Yorkers feel a great pride in the NYPD and the first responders. It was a difficult, emotional afternoon."

Goodell also acknowledged it was difficult to grapple with the reality that the NFL was specifically targeted in the attack, and the pain it has brought to the league's employees.