Football fans were shocked this week to learn that former NFL defensive end Chris Smith passed away this week at the age of 31. His cause of death is not yet known. 

According to ESPN, a statement regarding Smith's death was released on Twitter by the Cleveland Browns, a team he played for.

Smith remembered as "one of the kindest people"

The team said it was "deeply saddened" by his death and called Smith "one of the kindest people, teammates and friends we've had in our organization."

The statement went on to stress that the Browns' "thoughts and prayers are with his family during this difficult time."

We are deeply saddened by the passing of former Browns DE Chris Smith.

Chris was one of the kindest people, teammates and friends we've had in our organization. Our thoughts and prayers are with his family during this difficult time. pic.twitter.com/K8HySW4erM

— Cleveland Browns (@Browns) April 18, 2023

ESPN noted that Browns tight end David Njoku spoke up as well, tweeting, "Rest in paradise Chris Smith. Hometown hero and a brother to everyone. Such a kind soul. This is Heartbreaking."

XFL coach says fallen player "will be greatly missed"

Rest in paradise Chris Smith. Hometown hero and a brother to everyone. Such a kind soul. This is Heartbreaking

— Chief David Njoku (@David_Njoku80) April 18, 2023

Smith left the NFL in 2021 after a single season with the Las Vegas Raiders and then began playing for the XFL's Seattle Sea Dragons.

Jim Haslett is the team's coach, and he called Smith "a hard worker and an all around great person" who "will be greatly missed."

I am saddened to share that Chris Smith passed away earlier this week. Chris was a hard worker and an all around great person. He was an important part of our Sea Dragon family and will be greatly missed. My thoughts and prayers are with his friends and family at this time. pic.twitter.com/PKTvalisiZ

— Jim Haslett (@JimHaslett55) April 18, 2023

Smith lost his girlfriend in a 2019 traffic accident

Born in North Carolina, Smith played in college for the Arkansas Razorbacks before beginning his professional career in 2014.

In addition to playing for the Cleveland Browns, Smith also spent time with the Jacksonville Jaguars, Cincinnati Bengals, Las Vegas Raiders and Houston Texans.

Smith grappled with tragedy in 2019 when his girlfriend and the mother of his child lost her life after being struck by a motorist.

She had been riding as a passenger in Smith's vehicle and stepped out when a malfunction caused it to strike the road's median.