The NFL has confirmed that it has launched an investigation into the incident which saw Buffalo Bills offensive line coach Aaron Kromer arrested for assault and battery.
The 48-year-old was detained on Sunday after he allegedly punched a boy and shoved another following a confrontation over beach chairs in Florida.
Kromer was released on a bond and is awaiting a potential court date, but the league is keen to investigate the incident themselves in line with its policy on personal conduct.
"We begin an investigation as soon as we become aware of an incident," league spokesman Brian McCarthy told ProFootballTalk.com.
Kromer joined the Buffalo Bills earlier in the off-season.