(CNN) Already under scrutiny about a dog dying in an overhead bin and another dog being accidentally sent to Japan, United Airlines on Friday acknowledged its third animal-related mistake in a week.

A flight was diverted to Akron, Ohio, on Thursday after the airline realized a pet had been loaded onto the flight in error, airline spokeswoman Maggie Schmerin told CNN.

Flight 3996 was carrying 33 passengers from Newark, New Jersey, to St. Louis, but the pet was due to fly from New Jersey to Akron. United told CNN the unidentified animal was "safely delivered to its owner."

United said it offered compensation to all passengers as a result of the diversion. The airline declined to provide details about the compensation.

There were two earlier animal-related mistakes made by United Airlines this week.