Indiana University isn’t saying much about an order to one of its fraternities to halt all chapter activities.

Alpha Epsilon Pi is one of 30 Greek houses under quarantine — it had 25 coronavirus cases as of September 5. I-U isn’t saying whether the cease-and-desist order relates to violations of the quarantine or something else. The university is saying only that the letter was issued on Friday.

A statement from A-E-Pi’s national office calls it “a difficult and unfortunate situation” but doesn’t give specifics. The fraternity says it’s “working closely” with I-U administrators, Monroe County, and chapter leaders.