Veronica Aguilar
Veronica Aguilar, from Los Angeles, is charged with the murder of her sonPolice handout

An autistic 11-year-old boy was found dead and malnourished in a wardrobe after being locked away and sedated by his mother for three years, court documents show. Yonatan Daniel Aguilar, from Los Angeles, vanished in Los Angeles in 2013 with his battered body discovered in August this year.

The boy's mother, Veronica Aguilar, was arrested and has pleaded not guilty to murder. It is alleged that she told inquisitive neighbours and friends that he had been sent to live at an institution in Mexico, according to court records.

When Yonatan was discovered he weighed less than two-and-a-half stone, the average weight for a six-year-old, surrounded by cups of liquid medicine in the Echo Park neighbourhood. According to court documents the only people that knew their mother's dark secret was her three other children who were forbidden by their mother from saying anything, authorities say.

According to the LA Times, it has emerged that social workers, police and other officials lost track of the boy despite allegations of abuse before 2012. LA police investigating the case believed that he was so well-concealed by the 39-year-old that the boy's stepfather, Jose Pinzon, did not know the boy was living in the home.

It has been alleged that on 22 August this year Veronica said the boy had died with Pinzon believing that she would be travelling to Mexico to bury the boy. To his horror, the court documents say, he was led to an upstairs bedroom and to a tiny wardrobe where the boy's body was wrapped in a blanket and covered in pressure sores from lying on the tile floor.

According to the Times, cups of pink and red liquid were found near his body, and the boy had foam coming from his nose and was going bald. It was Pinzon who reportedly raised the alarm running to a nearby shop.

Pinzon told detectives that he had not seen the boy in several years. In front of police, Pinzon reportedly "immediately confronts the children that he had no idea that minor (Yonatan) was living in the house the whole time they were there," records state.

"I carry a photo of him in my wallet," he said. "I'm the only one that cared for him."

The LA Times reported that Yonatan's family had been the subject of six reports alleging possible abuse or neglect. One, in spring 2012, said teachers made two separate reports about him saying the boy came to school with a black eye and that he was hungry and hoarding food.