William Wolfe knocked at the apartment door and shot Virgil Walker, 49, and his wife, Kailey Walker, 30, "without warning," a Kalamazoo County sheriff's investigator said in an affidavit supporting murder charges last week.
Wolfe then returned to his Galesburg apartment, said goodbye to his cat and drove to another apartment complex before calling 911, according to the document.
Wolfe, 31, told investigators that the Walkers were too loud and he couldn't sleep, the sheriff's office said.
"It’s kind of shocking he said they were loud because they pretty much kept to themselves," said Jennifer Newman, another neighbor.
Investigators said Wolfe's mental health might have played a role.