The cause of death has not been determined, per the New York Daily News' Ebenezer Samuel.
"This is the worst possible news," former Giants teammate Beasley Reece said, per Samuel. "This is a great loss for the Giants. We lost one of the good guys. A quality guy. A giant of a man who could not have been nicer. This defies all reason."
The Giants selected Jeter with the fifth pick in the 1977 NFL draft after he was a consensus All-American in 1976 at USC. He went on to amass 200 tackles, 14 sacks, four fumble recoveries and two blocked kicks during his time with New York, per Eisen.
Following six seasons, the team traded him to the Los Angeles Rams.
Situated on the West Coast, Jeter made his presence felt with 45 sacks over the course of the next six seasons before closing his career with seven sacks during his lone campaign with the New England Patriots at 34 years old.
"He was built like a freak of nature," Reece added, according to Samuel. "He defied the stereotype of a football player as he was well-read and would engage in debates in the locker room. He was an eclectic individual."