. >> what detective renee swanson found was a macabre scene, the lifeless bodies of two children, a boy and a girl, tucked into their beds as if they were asleep. >> it was just like, you know, who could have done this to these children? could their parents have done anything like this to them? we really didn't know what we had. we knew that the parents were missing. >> detectives quickly learned that the apartment belongs to leigh ann barton, the wife of mark barton. what they don't know yet is that he is now waging war on the financial center of atlanta. >> i left the apartment to obtain the search warrant and then when we re-entered the apartment over to our left was like a table and it had a computer on the table and there was a note on the computer which we did not see at original entry and there was a letter from mark o. barton. >> in the letter barton wrote, "to whom it may concern, leigh ann is in the master bedroom closet under a blanket. i killed her on tuesday night. i killed matthew and michelle wednesday night." back in atlanta at all-tech investments, mark barton continues