The accident occurred in Irving, Texas. Glenn died just after midnight at Parkland Memorial Hospital, according to multiple reports.
Irving police told NFL.com that the cause of the crash is undetermined.
"Incredibly sad to hear about my buddy Terry Glenn," Glenn's former teammate Drew Bledsoe tweeted Monday. "Overcame a ton of adversity to become an excellent person. May your soul rest in peace my friend. #riptg88."
"I was pretty close with Terry and his rookie season was my first year here in '96," Patriots coach Bill Belichick told NFL.com. "I had a lot of interaction with him and the people that were involved in his life, his upbringing, separate form the Patriots. Terry is a very smart individual. Had a lot of obviously physical skill and talent. Could do a lot of things on the football field very naturally. I think he was deep down inside a good person with good intentions and a good heart. Obviously it's very unfortunate, very unfortunate passing and it's a sad day. Sad news."