at Da Nang, commanded by a lieutenant colonel, used 60 recon teams and two exploitation battalions (four companies of three platoons). Command and Control Central (CCC) at Kontum, also commanded by a lieutenant colonel, used 30 teams and one exploitation battalion. During 1969 404 recon missions and 48 exploitation force operations were conducted in Laos. To give an example of the cost of such operations, during the year 20 Americans were killed, 199 wounded, and nine went missing in the Prairie Fire area. Casualties among the Special Commando Units (SCUs – pronounced Sues), as the indigenous mercenaries were titled, were: 57 killed, 270 wounded, and 31 missing. Command and Control South (CCS) at Ban Me Thuot, also commanded by a lieutenant colonel, consisted of 30 teams and an exploitation battalion. Since the use of exploitation forces was forbidden in Cambodia, these troops were utilized in securing launch sites, providing installation security, and conducting in-country missions. During the year, 454 reconnaissance operations were conducted in Cambodia. The teams were ferried into action by RVNAF H-34 Kingbees and assorted U.S. Army aviation units in the Prairie Fire area, and by the USAF helicopters of the 20th SOS in the Salem House area. By the end of 1969, SOG was authorized 394 U.S. personnel, but it is useful to compare those numbers to the actual strengths of the operational elements. There were 1,041 Army, 476 USAF, 17 USMC and seven CIA personnel assigned to those units. They were supported by 3,068 SCUs, and 5,402 South Vietnamese and third-country civilian employees, leading to a total of 10,210 military personnel and civilians either assigned to or working for MACV-SOG. The mission of the Ground Studies Group was to support the sensor-driven Operation Commando Hunt, which saw the rapid expansion of the bombing of the Ho Chi Minh Trail. This was made possible by the close-out of Rolling Thunder, which freed up hundreds of aircraft for interdiction missions. Intelligence for the campaign was supplied by both the recon teams of MACV-SOG and by the strings of air-dropped electronic sensors of Operation Igloo White (the successor to Muscle Shoals), controlled from Nakhon Phanom. 1969 saw the apogee of the bombing campaign, when 433,000 tons of bombs were dropped on Laos. SOG supported the effort with ground reconnaissance, sensor emplacement, wiretap, and bomb damage assessment missions. The cessation of the bombing of the north also freed the North