Sean Gannon, a former Boston police officer and a UFC veteran who once fought Kimbo Slice in a street fight, has passed away.

Gannon’s death was first reported on social media as friends and family confirmed the sad news. MMA reporter Marcel Dorff also confirmed that Gannon has passed away. His age is unknown as is the cause of death, which has not been made available to the public yet.

https://twitter.com/BigMarcel24/status/1436718399736930308

One time UFC veteran Sean “The Cannon” Gannon has passed away. Gannon was a former Boston Police Departments Police Officer. He was also known for being the first man to ever stop Kimbo Slice in a streetfight. R.I.P. Sean Gannon.

Gannon (2-2) first competed for the Mass Destruction MMA promotion in 2003, where he went 3-0 as an amateur before turning pro at the end of the year. Gannon lost his first pro-MMA fight by submission but he was able to pick up two TKO wins in 2004. He was signed by the UFC in 2005 but lost his only fight in the promotion to Brandon Lee Hinkle at UFC 55. However, Gannon is most fondly remembered for his wild street fight with Slice.

Gannon was the first man to hand Slice a loss on the streets, which shows the reason why the UFC was willing to sign a fighter who had only a 2-1 record at that point in time. While everyone was talking about this street fighter named Slice at that point in time, it was Gannon who defeated him on the streets to get the shot in the UFC. While his career fighting for the world’s top MMA promotion didn’t pan out, there aren’t that many people who get to say they have stepped into the Octagon — the world’s ultimate proving grounds.

We here at BJPenn.com wish our deepest condolences to the family of Sean Gannon.