Mike Groll/Associated Press

Fans outside the Buffalo Bills' New Era Field were seen displaying anti-Colin Kaepernick imagery and selling T-shirts with similar sentiments ahead of Sunday's game between the Bills and San Francisco 49ers.

Robert Klemko of The MMQB tweeted a picture of two T-shirts that were being sold outside the stadium, including one that depicted a target on Kaepernick's chest:

The 49ers quarterback made his first start of the 2016 season Sunday—his first since his national anthem protest made headlines. Kaepernick has continually kneeled or sat during the anthem since the beginning of the preseason as a protest against racial injustice.

While Kaepernick's stance has drawn criticism, he had been a backup to Blaine Gabbert for the first five weeks. Returning to the starting lineup put Kaepernick back in the spotlight, which led to some Bills fans demonstrating their displeasure on a tackling dummy along with a pinata:

However, the messages were not all negative. A contingent of supporters stood outside the stadium with signs protesting police brutality and racial inequality, as ESPN's Josina Anderson noted:

During the week leading up to the game, Bills running back LeSean McCoy told reporters he hoped fans would be respectful toward Kaepernick:

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Be professional. Be respectful. You know right from wrong. He's a human being, he's a person. I think sometimes fans can get it confused that these athletes and superstars are not human and they are. He has feelings and he has a family. I'm not sure if he has children, but he has a mom and dad and you don't want nothing to happen to your children.

Kaepernick was booed before the game, and a loud "USA" chant took place in the stadium.

Follow Tyler Conway (@jtylerconway) on Twitter.