I was on duty the nights these events occurred. The vehicle first appeared over the alert patch (Cocked Alert Air Craft). I was one of the supervisors of a alert response team (Security 4). The craft (I believed at the time to be a "silent helicopter" as the vehicle was quiet, but had running lights that flashed at a set rate. The same colored lights and intensity that I associate with conventional aircraft display. The craft followed West to east on the North side of the runway, over flying the control tower and hangers to "Main Road." It turned south east, over flying the old abandoned weapons storage area (conventional bomb depot), spot lighting the area. A message to higher head quarters (Helping Hand) was generated by SSgt Stephonovich, NWSA Security Supervisor. A friend of mine (e-3) Motta was the Alpha Security Control radio dispatcher at the nuclear weapons storage area (NWSA). The craft circled the NWSA for several minutes. He told me the air craft hovered like a helicopter but there was no air craft noise. It hovered just above tree top level and turned a spot light directly into the Entry control point of the nuclear weapons control point. SSgt Stephonvich told me he responded to the entry control point and observed the vehicle and the light. This occurrence was in pitch black darkness, but you need to understand that the nuclear weapons storage area is surrounded by lights that turn the perimeter of the NWSA and all roads inside the NWSA to almost daylight conditions (day break). I departed the Alert Area to contact the Supervisor of Flying. His truck was parked just outside the Alert Area, on the taxi way to the main runway for the alert aircraft. There was at least 1 KC135 doing touch and go landings. I apprised the Supervisor of Flying (a Captain) that there is a air craft over the Nuclear Weapons Storage Area. I asked him to contact the air craft commander of the kc135 if he or members of his crew had visual contact or radar contact on this craft. The supervisor of flying contacted the kc135 and they replied they had both visual and radar contact. The air vehicle (UFO) (target in radar vernacular) was departing east into Canada. The target was trailed into Canadian air space by the kc135 but radioed back shortly that the target had disappeared off radar. Considering my frame of mind (silent helicopter), this was not unusual to me, not knowing that the radar operator meant that the target had not grounded it self, but flown at high speed out of range of the air crafts radar. (quite a different story). The next night the target returned to the base. (Mars Hill radar (NORAD)) notified the tower of a target approach. The tower notified csc (central security control) and an other Helping Hand was generated. There was great commotion over this. A Wing (Base) Alert was called. It turned out that Minot and an other SAC base in the pan handle of Michigan were also being probed. We initially felt the target was the air force testing the bases (personal opinion) to check for security response and appropriate response. At the time the USAF had received threats from radical groups (weathermen, black panthers and dissident native Americans who were demanding that northern Maine be returned to the tribe. On the third night, 2 helicopters from Bangor Maine ( a army reserve base), were attached and our 10 man response force was divided between the two copters. E2 Johnny Nunze was assigned to the m-60 on one of the hilos. He observed the target and asked for permission to fire upon it when it began to buzz the Nuclear Weapons Storage Area. Tsgt Adair the Security Flight Chief denied authority. Tsgt Adair was outside his vehicle that was parked just outside the entry way to the Nuclear Weapons Storage area. He radioed he was being illuminated by a spot light from the target or helo that was above him. He demanded CSC to have the air craft control tower identify the craft hovering over his head. The craft remained over his position for several minutes but left at a slow speed back over the NWSA. I do believe TSgt Harry Adair would have fired upon the target had clarification been swiftly forth coming. It was the target. The target rose to the same air space as the two army guard helos and all hell broke out as far as radio communications. You have to remember. This is a Priority A resource. Deadly force is authorized. All three crafts are in close proximity to one an other in pitch darkness with blinding light below them from the perimeter lighting below. For at least an hour there was chaos and then the target flew east into Canada again. The border was 10 miles or less as the crow flies from the NWSA. After things cooled down, the base Staff Judge Advocates Office came to Commanders Call to tell us that it was a good thing we hadn't fired on the craft as we had no legal right to do so. I beg to differ. I was assigned to protect Priority A Resources and if anyone refused to obey any instruction they were issued by me or members of my security team, great bodily harm or death would result. On several different occasions, my security team responded to Helping Hand situations where the parties involved just didn't want to co-operate and they were physically restrained. Physical restraint by Security Personnel can be very hazardous to ones health. Ask any alert crew member of the air craft we were assigned to protect will tell you and any one else who violated standards of protocol. The Security Police Squadron Commander (Col. Martin) had a poster behind him, prominately positioned above his head as he sat at his desk. The drawing is poster size. There is a Gorilla in a stretched out Security Police Uniform. He is holding a smoking m-16 pointed at you in his right hand and an obviously upset chuwawa barking at you, leashed to the gorillas' left hand. Captioned below is. "Halt!! Who was there??" Considering the average age of these sentry's was 20, I understand the Col.'s humor.