ANN ARBOR, Mich. (AP) — Michigan canceled this weekend’s game against Maryland because it had at least 12 positive COVID-19 cases within the football program, a person familiar with the situation told The Associated Press on Thursday.

The size of the outbreak has not been disclosed by the school and the person spoke to The AP only on condition of anonymity. The person did not know the number of players, coaches and staff members who were among the positive cases from testing on Sunday and Monday, nor did the person know how many players and coaches might be affected by contact tracing quarantine protocols.

While outbreaks have disrupted more than 100 games across major college football since late August, the problems with the Wolverines are being closely watched in part because they could put next week’s rivalry game at No. 3 Ohio State in jeopardy.

Ohio State (4-0) has missed two games already in this pandemic-shortened season.