A Scottish Ambulance Service helicopter was among emergency services called to the scene near Dunblane.
Two men have been seriously injured after an Army truck crashed and landed on its roof at the Keir Roundabout near Dunblane.
Emergency services were called to the incident shortly before 09:45.
The men, aged 33 and 21, were taken to hospital with serious, but non-life-threatening injuries.
A Scottish Ambulance Service helicopter was scrambled to the incident, as well as four fire appliances and a heavy rescue unit.
The A9 was closed southbound while emergency services dealt with the incident.
Police said the vehicle had been travelling south on the A9 prior to the crash.