Philadelphia Eagles quarterback Michael Vick has been forced to cancel a series of book-signing dates because of death threats.
"Despite warnings of planned protests, Vick had hoped to continue with the appearances as planned, bringing his story of redemption and second chance to major markets," Worthy Publishing said in a statement.
"However, once the reported protests escalated into threats of violence against the retailers, Worthy Publishing, Vick and his family decided to cancel the events."
Vick was going on the book tour to promote his autobiography "Finally Free," which details his life as a football player and talks about the 18 months he spent in prison after pleading guilty to dogfighting charges in 2007.
"It is disturbing that a few extremists would threaten Vick's family and store employees," said Vick's spokesman, Chris Shigas.
"Michael Vick has millions of fans and has countless letters from teachers thanking him for inspiring students to make positive change."