More than two months after the disappearance of two young siblings in rural Nova Scotia, RCMP report their “intensive” investigation has included reviewing some 5,000 video files and more than 600 public tips — but the case remains unsolved.

Lilly Sullivan, 6, and her brother Jack Sullivan, 4, were reported missing on May 2 from their home in Lansdowne Station in Pictou County.

In a Wednesday update, RCMP said they are conducting forensic examination on “materials” found during ground and air searches, including on a pink blanket that officers seized.

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“The blanket was located and seized very early in the investigation. It was outside and found near Lilly and Jack’s home,” spokesperson Cpl. Carlie McCann told reporters.

“The family has confirmed that the blanket belonged to Lilly. Police are investigating if and how it relates to her and her brother’s disappearance.”

The children’s family had indicated the siblings wandered away that morning from the home, which is situated in a heavily-wooded and rural area.

The case, led by the Northeast Nova RCMP Major Crime Unit, involves RCMP units in Nova Scotia, New Brunswick, and Ontario, along with the National Centre of Missing Persons, and Canadian Centre for Child Protection.

Police agencies from other provinces and municipalities in Canada have also contributed to the efforts.

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As part of the investigation, RCMP have applied for authorizations and warrants to seize and examine materials and devices. A forensics lab in Ottawa is assisting the forensic identification units in Nova Scotia, McCann said.

RCMP said they have reviewed about 5,000 video files that they received by canvassing Lansdowne Station and the surrounding areas. In May, police confirmed they had video evidence that showed the children with their family in public the day before they were reported missing.

RCMP also said they’ve formally interviewed more than 60 people and administered some polygraph tests. The children’s stepfather, Daniel Martell, has told Global News that he has taken a test. 

“Right now, there are more than 800 tasks associated to this investigation,” said Staff Sgt. Rob McCamon, the acting Officer in Charge of Major Crime and Behavioural Sciences, in a release.

“A tremendous amount of careful, deliberate investigative work is underway by people here at home and in other parts of Canada; our collective efforts will continue every day until we determine with certainty the circumstances surrounding Lilly and Jack’s disappearance.”

The children’s disappearance was added to the province’s Major Unsolved Crimes Program, which offers a reward of up to $150,000 for information in the case.

Anyone with information can call the Northeast Nova RCMP Major Crime Unit at 902-896-5060 or submit a tip anonymously through Crime Stoppers.

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