If this only occurred on the ports connected to APs, and it occurred following a brownout, it is possible that the brownout (or recovery from the brownout) on AC power cabling that runs near the data cables feeding the APs caused a current to be induced on the ethernet cabling leading to the APs, backfeeding the ports on the switch.
Was the fault condition 'UV/OV Fault'? If so, this would indicate that the switch put the port into the faulted state for either an under-voltage or over-voltage event.