On the Yankees official news feed Thursday, there was a false item about Derek Jeter undergoing a sex change.
The Cubs' page contained an expletive directed at longtime Cubs fan and actor Bill Murray. The posts were removed shortly after appearing.
MLB released a statement saying "for a brief moment today, a few MLB Club Facebook accounts were hacked and inappropriate material was briefly on display."
The league also said it is working with Facebook and legal authorities to determine what happened.