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Increasingly politically minded 49er Colin Kaepernick may cause a further problem for the 49ers' season in Santa Clara as the Santa Clara Police Officers Association is now threatening a boycott of Levi's Stadium. As CBS 5 reports, the police union sent a letter to the team Friday saying that Kaepernick's ongoing protest over police brutality and his broad statements about law enforcement "threatened our harmonious working relationship” and "If the 49ers organization fails to take action to stop this type of inappropriate behavior it could result in police officers choosing not to work at your facilities."

Kaepernick upped the ante Friday in his protest over racial injustice and police brutality, pledging to give the first $1 million he makes this season to organizations assisting communities most affected by these problems. As ABC 7 reported, the 28-year-old Kaepernick sounds emboldened by the attention he's gotten for refusing to stand for the national anthem, and says he's "actively trying to make a change" and this isn't all talk.

As the Chronicle reports, Kaepernick continued making public statements earlier in the week that were disparaging to law enforcement, such as, "You can become a cop in six months and don’t have to have the same amount of training as a cosmetologist. That’s insane. Someone that’s holding a curling iron has more education and more training than people that have a gun and are going out on the street to protect us.”

Kaepernick also appeared on the field wearing socks depicting cops as pigs in early August.

Typically bombastic San Francisco Police Officers Association President Martin Halloran also responded with a letter to 49ers owner Jed York, calling Kaepernick's comments “foolish” and saying they showed his “naivety and total lack of sensitivity towards police officers."

About 70 Santa Clara officers regular staff Levi's Stadium, and it remains to be seen how real this boycott threat is.

Update: The Santa Clara chief of police, Michael Sellers, tells KOLO-TV that he'll mediate between the police officers' union and the 49ers and try to find a solution.

Previously: 49ers' Kaepernick Will Continue To Sit During National Anthem To 'Stand With The People'