The army officer seemed to be after information about a missing alien.
He is a tall Caucasian male with with reddish-brown hair and a commanding presence. He wears a military uniform with an assortment of ribbons on his chest.
He was a hired actor, and his army officer act was just a role. He knew nothing of real military matters or he wouldn't have made elementary mistakes like wearing a Korean war decoration he was too young to have earned, or driving a Humvee with no army insignias on it.
Scooby-Doo! (DC Comics)
He was hired by tabloid publisher Everett T. Trusdale to lend credibility to the idea that the U.S. Army had found a UFO. He chased tabloid writer Dave Segal, supposedly to find out where the missing alien was hiding. The gang quickly exposed him as an impostor.