Robert Hawkins was a depressed teenager who believed he had endured a terrible fortnight when he snapped, took a rifle, and killed eight Christmas shoppers before shooting himself.

Two weeks ago his long-term girlfriend dumped him. Last week he was sacked by McDonalds over a missing $17. He was also awaiting a court case due later this month for underage possession of alcohol.

The 19-year-old lived with a family in the middle-class town of Bellevue, Nebraska. The small town, which is sandwiched between the city of Omaha and a US military base, proudly boasts of its tight-knit community.

Hawkins moved into the suburban home of Debora Maruca-Kovac after becoming friends with her two sons, aged 17 and 19.

Mrs Maruca-Kovac said her family had taken him in after he had fallen out with his stepmother. Court records show that at least once he was termed a ward of the state meaning he had been legally removed him from his parents’ custody - possibly to be held in a juvenile detention centre.

“When he first came in the house, he was introverted, a troubled young man who was like a lost pound puppy that nobody wanted,” Mrs Maruca-Kovac said.

Hawkins had dropped out of Papillion-La Vista High School without qualifications and a criminal record that included one drug conviction and several misdemeanour cases. His most recent arrest for underage possession of alcohol came 11 days before his shooting spree.

Since leaving school he had got a steady job, passed his driving test and earned a high school equivalency degree. Mrs Maruca-Kovac thought he was improving.

“He was depressed, and he had always been depressed,” she said. “But he looked like he was getting better.”

Mrs Maruca-Kovac is a medical nurse and she explained that Hawkins had been treated for attention deficit/hyperactivity disorder and depression but was not taking any medication. She said he also had a drinking problem and would occasionally smoke marijuana in his bedroom.

She spoke to Hawkins just before his shooting attack and found the suicide note he had left. “I was fearful that he was going to try to commit suicide but I had no idea that he would involve so many other families,” she said.

Mrs Maruca-Kovac described the note in which he said “he was sorry for everything, that he didn’t want to be a burden to anybody, he loved his family, he loved all of his friends. He was a piece of shit all of his life and now he’ll be famous."

By the time the nurse had discovered the truth she had already seen many of Hawkins's victims, who had been rushed into the medical centre where she works.

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