Crosbie said that in one incident, a parent approached a league official “aggressively” after being asked to move away from an area beside the pitch reserved for players and team staff.
He said several games were abandoned during the opening week because of “team officials looking to go fighting with other team officials”.
One team official had to be removed from a match because he was not registered with Disclosure Scotland’s Protecting Vulnerable Groups (PVG) scheme – which is a legal requirement in regulated roles like teaching or sports coaching.
Crosbie said that discriminatory language had been used by players against other players, and by adults against minors.
The email also highlighted “team officials threatening minors”.
Police are involved in one case following reports that threats were made during a game and that possible hate-related language was used.
The league’s executive and disciplinary committees are now reviewing the cases and fixtures could be suspended for some teams and clubs as a result.
No individuals, teams or clubs have been named while investigations continue.
The Scottish Youth Football Association have been approached for comment.