The Mass. Gaming Commission dinged all three of the physical casinos it oversees on Tuesday for taking illegal bets on Massachusetts college sports at their sportsbooks, levying a cumulative $50,000 in fines for violations that occurred in the earliest days of legal sports wagering here.

Plainridge Park Casino in Plainville was fined $20,000 for taking bets on a Feb. 2 regular season men’s basketball game between Merrimack College and Long Island University, MGM Springfield was hit with a $20,000 penalty for offering action on regular season Harvard men’s basketball games on Feb. 3 and Feb. 4, and Encore Boston Harbor in Everett was fined $10,000 for taking a bet on a Feb. 2 regular season game involving the Boston College women’s basketball team.