AL ASAD, Iraq -- Patrolling the perimeter of the base, all seems clear. Suddenly, a call comes in through the crackling radio and a daily patrol turns into a not-so-routine encounter. "Unusual activity near the fence line," came over the radio. Members from the Quick Reaction Force, 4th Low-Altitude Air Defense Battalion, Security Battalion, Marine Wing Support Group 37, 3rd Marine Aircraft Wing, respond immediately to the call.Within minutes, the reaction force is at the site and the conflict is resolved. Suspects are detained, and all take a deep breath. For the Marines manning the QRF, each call is as tense as the last. The Security Battalion is an amalgam of reserve and active duty units covering a variety of occupational specialties, including air defense, artillery, infantry, and military police.The duty of operating the QRF has been assigned to Marines from Battery P, 5th Battalion, 14th Marine Regiment, 4th Marine Division based in Spokane, Wash.Initially, the former artillery Marines were stunned by their sudden job transition upon arriving because serving with the base security force isn't exactly what they thought they'd be doing here."When I heard that I'd be part of a security unit I was pretty shocked," said squad leader Sgt. Mackenzie R. Anderson, field artillery cannoneer, QRF "I was even more surprised when I got here and was assigned to QRF."However, Anderson and his fellow Marines weren't totally unprepared. Two months of training at Marine Corps Air Ground Combat Center, Twentynine Palms, Calif., preceded their deployment."We learned all different kinds of infantry training," said the 26-year-old native of Moscow, Idaho. "That really helped us get ready for this."With the high level of danger in Iraq, proper training was extremely important for the security Marines."We didn't cut any corners in the training of these guys," said Staff Sgt. Joe Bowman, platoon sergeant, QRF. "It's a huge change from artillery to security, and it took a lot of work."With the high level of success the Marines have had in the past few weeks, it seems the hard work paid off."We've already detained quite a few (Iraqi nationals) trying to steal from (the base)," said Cpl. Jeron V. Smith, field artillery cannoneer, QFR. "Most were on motorcycles, but they stopped real soon after they saw us getting close with the HMMWVs."The 24-year-old's first time performing his current duties has been action-packed, yet the Tacoma, Wash., native has taken it in stride."The first week we were here we got calls nearly every day," said Smith. "Staying calm is the most important thing."Yet, even for Marines with the best training and strong spirits, the responsibility of handling potentially dangerous situations can still be intimidating."The first few times we went out (to answer an emergency call) it was a bit scary," admitted Anderson. "We've gone out so many times now it's slowly becoming routine."According to Anderson, even though they have become more comfortable with their job, it is far from being monotonous. "Every situation is different and needs to be handled carefully," said Anderson. "We take the security of this base very seriously."