The suspect's name has not been released and the victims have been identified only as a major and a sergeant major who worked as recruiters based in Jackson, Tenn., WMC-TV, Memphis, reported.
The suspect was taken into custody by colleagues before police arrived at the scene of the shooting, which occurred about 12:45 p.m. CDT in a parking lot at the National Guard Armory, near Naval Support Activity Mid-South.
"I'm sure there could have been more injury if they hadn't taken him in custody or gotten him restrained," Millington Police Chief Rita Stanback said.
The base was put on lockdown after the shooting but the lockdown has been lifted, the report said.
WHBQ-TV, Memphis, citing a law enforcement source, reported the alleged shooter was relieved of duty and went to his car, got a small handgun and opened fire.
One of the victims was reported shot in the foot and the other in the lower leg.
Tennessee National Guard Maj. Gen. Max Haston said one of the victims served in Iraq in 2005 and the other may have served in Afghanistan.
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