TAMPA, Fla. – Local law enforcement agencies say they are investigating reports of a loud "boom" heard across Pasco, Polk and Hillsborough counties on Saturday, but as of yet, there has been no official word of a cause.

Our partners at The Tampa Bay Times said they might have found a possible culprit.

We spoke with officials at MacDill Air Force Base, and they say it was not caused by any of their aircraft.

Our partners at The Tampa Bay Times said they spoke with Eglin Air Force Base, Tyndall Air Force Base, the 45th Space Wing and Kennedy Space Center, and they all said it wasn't them.

But they did learn two F-15 fighters were given permission by NORAD to fly at supersonic speed — in excess of 760 mph — over the Gulf of Mexico.

NORAD is the North American Air Defense Command.

The jets were not responding to any incident, Canadian Air Force Lt. Marco Chouinard told the Times. There was no way to be sure they caused the noise, he said.

For more, read the Times report.