“You are not going to change us, you know that, right?” Mr. Trybus, 62, says to Ms. Irizarry, 24, as he walks up to her. “Are you a United States citizen? Then you should not be wearing that.”

Ms. Irizarry, who was at the park with friends for a birthday party, can be heard on the video telling Mr. Trybus that she is indeed an American citizen. Her friends can be heard telling him that Puerto Rico is part of the United States. At one point in the video, Ms. Irizarry tries to move away from Mr. Trybus and walks out from under a pavilion, but he follows her as Officer Connor appears not to approach them.

“Officer, officer, I feel highly uncomfortable,” Ms. Irizarry tells Officer Connor, who does not appear to respond to her as he is addressed, and can be seen turning his back and walking toward his police car.

The video shows Mr. Trybus continuing to confront Ms. Irizarry and her friends for about 10 minutes before additional police officers arrive and eventually arrest him. Mr. Trybus was charged with disorderly conduct and assault, the Forest Preserve District said in a tweet. He could not be reached for comment on Tuesday afternoon.