Buffalo Bills running back CJ Spiller has thanked the organisation for their support during a family tragedy.

Spiller missed the last week of practice having been granted leave following allegations that his step-grandfather shot four people in Union County, killing two, before committing suicide.

The 26-year-old returned to the team on Sunday and was quick to express his gratitude for the way that the Bills supported him through a tough time.

"The way they send their support, their thoughts and prayers to everybody involved because if you don't know, my hometown is a 1,900 population," Spiller told reporters.

"It's a small community, so when they wanted to send their condolences down to all of Union County, it speaks volumes about the organization that we have here.

"The supporting cast of Coach [Doug] Marrone, our CEO Russ [Brandon] and our general manager Doug Whaley; I was texting those guys, checking up on them, they were checking up on me. I was letting them know I was pretty good."

Spiller has already reassured fans that his main focus is on football ahead of their first match of the new season, which comes against the New England Patriots on Sunday.