Hamburg Police Lt. Bob Krone said the accident happened Friday afternoon and is still under investigation. He didn't provide any other details. The accident occurred after the Bills' final practice of a three-day minicamp.
Dareus is already facing charges in Alabama where he was arrested last month for possession of synthetic marijuana and drug paraphernalia. He called it a youthful mistake.
His agent, Todd France, didn't immediately return a message seeking comment.
Dareus was selected third overall in the 2011 draft and is in his fourth season with the Bills. The 24-year-old played for Alabama.
The Buffalo News first reported the accident on its website Monday evening.
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