A young boy showed up on a neighbour's doorstep with marks on his wrists, rug burns and a protruding ribcage more than a year before his RCMP father and stepmother were arrested on abuse charges — and police returned him to his home, an Ottawa court heard Thursday.

"There was fear and sadness in him," testified the woman who lived at the home, and whose own young daughter opened the door for the boy.

"I was heartbroken watching him. My instinct was to hold him and comfort him," she told the court.

Charges laid in 2013

The boy's 44-year-old Mountie father and his 36-year-old stepmother, neither of whom can be named to protect their son's identity, were charged in February 2013 in what Ottawa police have called the "worst case of abuse police have seen."

The father and stepmother are both on trial for aggravated assault, forcible confinement and failing to provide the necessaries of life. The woman is also charged with assaulting the child with a weapon, while the man is charged with sexual assault causing bodily harm and assault with a weapon.

The RCMP has confirmed that the father has been on leave since May 2011, but the reason for that remains under a court-ordered publication ban.

The woman who took the stand Thursday, who also cannot be named, said the boy, now 13, came to her door in November 2011, more than a year before his parents were charged.

She testified Thursday that she noticed what looked like ligature marks on his wrists, and that his forearms and most of his stomach were covered in what looked like rug burns. As well, the boy's stomach was "sunken" and she could see his ribcage, she testified.

No food for two days, court hears

The boy told her he had to do 600 push-ups before he could eat and that he hadn't had a meal in two days, the woman testified. She gave him cake and a glass of milk and called police, who took the boy home, she said.

When police returned later, however, they said the boy had exaggerated what happened and that there was food on his table at home, the woman testified. She added that, at the time, she figured the officers had done the right thing.

The court has previously examined 160 photos of the scarred, emaciated boy when he was admitted to the Children's Hospital of Eastern Ontario in 2013, as well as cell phone videos from 2013 of the boy naked and restrained in the basement of his family's home.

Former teachers, principal testify

Three of the boy's former teachers and a school principal have also testified over the past two days that the boy was a polite student who seemed happy.

That characterization stood in contrast to how the parents portrayed the boy in private meetings, where they suggested he was a liar who engaged in bad behaviour, court heard.

Earlier in the trial, the court watched a police interview video with the boy's stepmother in which she told an Ottawa police officer that her stepson was stealing and getting into fights, and that he began being home schooled in 2012.

The educators testified that they did witness the boy push a student, take another student's snack and touch a girl's hair — but that those incidents were not unusual for someone that age.

The trial is now adjourned until October.