Updated

As a teenager, Adam Lanza would come in for a haircut about every six weeks without speaking or looking at anyone and always accompanied by his mother, said stylists at a salon in the town where Lanza gunned down 27 people last week, including his mother, before killing himself.

He stopped coming in a few years ago, and the employees at the salon thought he had moved away, said stylist Bob Skuba.

The comments from him and his colleagues were among the first describing how the Lanzas interacted with each other. Investigators have found no letters or diaries that could explain the attack, one of the deadliest mass shootings in U.S. history.

Cutting Adam Lanza's hair "was a very long half an hour. It was a very uncomfortable situation," stylist Diane Harty said. She said that she never heard his voice and that Nancy Lanza also hardly spoke.

Another stylist, Jessica Phillips, echoed their descriptions of the Lanzas and added that Nancy Lanza would give her son directions about what to do and where to go.

Adam would move only "when his mother told him to," Skuba said.

"I would say, 'Adam, come on.' He wouldn't move," Skuba said. "And his mother would have to say, 'Adam, come on, he's ready.' It was like I was invisible." He said Adam also wouldn't move from his chair after his hair was cut until his mother told him to.

If a stylist would ask Adam a question, Skuba said, his mother would answer.

"He would just be looking down at the tiles ... the whole time," Skuba said.

Former classmates have previously described Adam Lanza as intelligent but remote, and former high school adviser described him as anxious and shy. Several people who knew his mother have described her as a devoted parent.

Divorce paperwork released this week showed that Nancy Lanza had the authority to make all decisions regarding Adam's upbringing. The divorce was finalized in September 2009, when Adam Lanza was 17.