The father of Kienan Hebert says he intentionally left the family home unlocked on the night that his son was safely returned after a harrowing, four-day ordeal.

Kienan Hebert disappeared after being put to bed on Tuesday night, and wasn't seen or heard from until Sunday, when he was secretly returned to his home in Sparwood, B.C., by a suspect at about 3 a.m. local time.

The boy's safe return has been called a miracle by his family and police, but it has also raised questions about how the suspected abductor was able to get inside the house undetected.

While the boy's father, Paul Hebert, said that he had left his home unlocked on purpose that night after issuing a public plea for the boy's return, he declined to say if the decision to leave the home open was based on advice from police.

"We asked (the suspect) to bring him back to a safe place, and he brought him back to our house," Hebert told The Canadian Press.

Several hours before, at around 3 a.m., police received a 911 dispatch call suggesting the boy would be at his family home, which was empty at the time. The Hebert family moved into a neighbour's house shortly after their son was reported missing and their home was designated as a crime scene.

Police arrived at the home to find Kienan sitting alone on a couch with a blanket. There was no suspect on the premises.

Police have since admitted that the boy's return to the home was unexpected.

"In the middle of the night, the child was returned, as were our wishes, but to great surprise, to a location we never would have thought, and the child ended up in the vacant home," RCMP Cpl. Dan Moskaluk told CTV News Channel Monday.

The suspected abductor, 46-year-old Randall Hopley, has so far evaded officers and remains at large, but police have asked him to come out of hiding.

"Randy, we just want to talk to you," Moskaluk said in a news conference Sunday. "What we've got left to do is speak with you. It's very, very important that we speak to you right now."

Earlier, Hopley's mother issued a tearful plea for her son to come home following the incident, which triggered an Amber Alert and was the focus of intense, nationwide media attention.

And on Monday, Moskaluk declined to offer details on how someone managed to get into the Hebert home on two occasions: first, to abduct the child and second, to return him safe and sound.

"With respect to the home, again the RCMP's number one priority was the safe return of Kienan and steps were taken to facilitate that. We cannot discuss any of the details at this time as to how things unfolded here," he said.

Moskaluk said police are being cautious about divulging any investigative details about why Hopley is considered a suspect.

"At this point in time, if Randall Peter Hopley was seen by a police officer he would be placed under arrest, we would have the grounds to arrest him," Moskaluk would only say.

He also cautioned news outlets against broadcasting sensitive details, such as the location of police checkpoints, which could help the suspect evade capture.

The boy's father said that his boy, one of eight children in the family, is doing well.

Meanwhile, police stepped up the hunt for Hopley, who the RCMP say is the sole suspect in the kidnapping.

The toddler was returned to his home unharmed early Sunday morning after vanishing from his bed four days earlier. But Hopley remains at large and police are searching the area in and around Sparwood on foot, on ATVs and by air.

Police said they are still looking for Hopley's brown 1987 Toyota Camry, although they say he may have switched vehicles.

Hopley has a history of criminal behaviour, including a conviction for sexual assault two decades ago.

In a 2007 incident, Hopley was charged with break and enter, unlawful confinement and attempted abduction.

While court records show that the case involved a child under the age of 16, all of the charges were stayed, except for the break and enter.

With files from The Canadian Press