Pictou County (Canada) - A nightmare that never ends: For over a week, there has been no trace of siblings Lily (6) and Jack Sullivan (4). The two children disappeared without a trace on Friday morning. There is now hardly any hope.

Police believe they ran out of the house in rural Pictou County unnoticed, The Guardian reports.

Mother Malehya Brooks-Murray heard her children playing before she fell asleep again. When she woke up, Lily and Jack were gone.

A large-scale search operation was immediately launched in the dense woods surrounding the house. Dozens of helpers combed the area.

The search proved difficult due to the rough terrain. A shoe print briefly gave the search teams hope, but the police announced that there was little evidence that the children were in the woods.

The search for them has since been drastically scaled back."The likelihood that they are still alive is very low," explained police spokesman Robert McCamon. The investigation is also looking into the possibility of foul play.

Stepfather Daniel Martell said he alerted the police immediately - and searched non-stop himself. "Hardly any evidence since the first day. It's unbelievable that nothing else has been found," he said.

He is said to have been questioned by the police for around four hours. He was asked to reconstruct the day the children disappeared and the days leading up to the incident.

"My story has always been consistent. If you tell the truth, it's always consistent," he said later.