Emergency services have been called to an incident at an RAF air weapons range.
Police went to RAF Tain on the Dornoch Firth, in Easter Ross, at 5.55pm on Tuesday to investigate reports of an incident.
The range is used by the RAF and the army and has a rifle range and small arms range as well as bombing ranges.
An Army spokesperson said: "We are aware of an incident at the Tain base, near Inverness.
"We will release more information as and when it becomes available. It would be inappropriate for us to comment further at this point."
Police said officers were at the scene.
A Police Scotland spokesman said: "Police are currently in attendance at RAF Tain following reports of an incident.
"A call was received by police at 5.55pm and officers are at the scene."