Passengers on a flight leaving Hartsfield-Jackson Atlanta International Airport had a scary situation after police say they found a loaded firearm magazine on board their aircraft.

Atlanta police say they received a call around 4:30 p.m. on Nov. 9 after a passenger discovered the magazine near seat 7A of the Airbus A320.

Investigators say the loaded magazine contained 10 hollow-point rounds and was marked with the initials "K.H."

According to police, the flight was on a turnaround route between Cincinnati and Atlanta, and the magazine was found during the boarding of the flight back to Ohio.

After deplaning the passengers and crew, law enforcement thoroughly searched the aircraft and did not find anything of concern. TSA agents re-screened the passengers, and the flight left the Atlanta airport a few minutes before 8 p.m.

A Frontier spokesperson told CBS News Atlanta that the ammunition "belonged to a law enforcement officer who was on an earlier flight on the same aircraft." 

"The ammunition and magazine were taken into the custody of the Atlanta Police Department and the property owner was referred to Atlanta P.D. to retrieve his items." the spokesperson said. Officials have not confirmed their statement.

Authorities say the FBI was notified of the situation but did not find any active threats.

The investigation into who left the magazine remains ongoing.