CSN Philly brings us video of the altercation:
UPDATE: Jeff McLane of Philly.com gives us some details on what was said during the fight:
Williams used a racial slur during the incident, according to an Eagle that was near the altercation.
According to the player, Williams said to Cooper more than once, "I'm not a n---- you [mess] with."
---End of update---
McLane and CSN Philly's Geoff Mosher talked to both players after practice.
Per McLane and Philly.com:
The altercation began after the two were matched up in one-on-ones. Williams and Cooper got into each other's face and then a few players stepped in and tried to break it up. They were clenched together for several moments until cornerback Brandon Boykin was the first to step in.
Williams had to be forcibly pulled away. The fiery cornerback then walked to a separate field and strolled up and down by himself.
Cooper looked visibly distraught and stayed out of one-on-one drills that involved receivers and defensive backs until DeSean Jackson came over to him. Jackson eventually walked over to Williams and had a conversation.
Cooper was caught on tape using a racial slur during a Kenny Chesney concert in June and, according to CBSSports.com, Williams later said there was an "elephant in the room" in regard to the incident.