( CNN ) -- Police continued their investigation Tuesday into the shooting deaths of an Army recruiter and a 17-year-old girl in Maryland that appear to be `` a murder-suicide , '' Montgomery County police said . Staff Sgt . Adam Anthony Arndt , 31 , knew Michelle Lynne Miller because he supervised her recruitment as she planned to enlist in the Army Reserves after graduating high school , police said . Police found both of them dead Monday inside Arndt 's apartment in Germantown while looking into a report of a missing juvenile possibly being at that location , police said . Police broke down the door because they were unable to make contact with anyone inside . `` Detectives now believe that Arndt shot Miller and then shot himself , '' police said in a statement . Miller was a senior at Rockville High School , police said . Miller 's father , Kevin , told CNN affiliate WJLA that he believes his daughter was lured to Arndt 's residence after she received a call Sunday night from Arndt , who was threatening suicide . His daughter raced to his home in her mother 's car , her father said . Miller had just been accepted at Arizona State University and enlisted to help pay the tuition , her father said . She wanted to be a psychotherapist , he said . Arndt was apparently in violation of Army recruiting regulations because a recruiter is n't `` allowed to have anyone who would be considered influenced by your position in the Army in your private home , in your dwelling place , '' said Kathleen Welker of the U.S. Army Recruiting Command . When asked if the recruit 's presence in Arndt 's residence violated regulations , Welker stated : `` I would say it appears that way . But it is being investigated by the police and by our Criminal Investigation Division . '' A recruiter is also prohibited from having any sort of relationship with someone applying for military service , Welker said . Arndt worked at the recruitment center in Gaithersburg , Maryland , she said .
An Army recruiter shoots a recruit , 17 , and then himself , police say . Staff Sgt . Adam Anthony Arndt , 31 , supervised the recruitment of Michelle Miller . Her father says she raced to the home of Arndt , who threatened suicide . She wanted to become a psychotherapist , her father says .