Surrey Police has issued a statement after a video apparently featuring the father and stepmother of Sara Sharif was shared by the BBC today.
Ten-year-old Sara's body was found at her home in Horsell, Woking, on August 10.
Surrey Police want to speak to her father Urfan Sharif, his partner Beinash Batool and brother Faisal Malik in relation to her death.
A low-quality video was sent to the BBC, in which a woman believed to be Sara's stepmother Beinash says the schoolgirl's death was an 'incident' and offers to cooperate with British police.
A travel agent spoke with Woking News and Mail explaining how all three had booked a one-way flight to Islamabad, Pakistan on August 9 - a day before the 10-year-olds body was discovered.
Responding to the video in a statement released this afternoon, a Surrey Police spokesman said: "The investigation following the death of 10-year-old Sara Sharif in Woking on August 10 has been fast-moving, challenging and complex.
"Following the tragic discovery of Sara’s body at her home in Hammond Road, we identified three people we wanted to speak to as part of our investigation into her death, Sara’s father, Urfan Sharif, 41, his partner Beinash Batool, 29, and Urfan’s brother, Faisal Malik, 28.
"We were made aware this morning (Wednesday), of a video apparently featuring Urfan Sharif and Beinash Batool that had been obtained by the UK media, in which Beinash Batool suggests that the family may be willing to cooperate with the British authorities.
"Clearly this is significant, and we have been liaising with our international partners, including Interpol, the Foreign, Commonwealth and Development Office and the National Crime Agency, to determine the next steps.
"As you will appreciate, progressing these enquiries through the appropriate channels has to be handled carefully and sensitively.
"The welfare of the five children who travelled to Pakistan on August 9 is a priority for us.
"We remain absolutely committed to conducting a thorough investigation into Sara’s death. Any co-operation from the people we want to speak to will assist the enquiry."
In the video, Sara's father Mr Sharif does not speak while Ms Batool reads from a notebook.
Ms Batool spends only two sentences of the 2 minute and 36 second-long video on Sara, describing her death as an 'incident'.
The rest of the video focuses on how the media have "been giving wrong statements and making up lies" about Sara's death.
Ms Batool said her entire family have been affected and the reason they have gone "into hiding" is "out of fear for their safety".
Throughout the video Ms Batool makes allegations against the Pakistan police. Claiming they are harassing the couple's extended family, illegally detaining them and raiding their homes.
In response Jhelum police chief Mehmood Bajwa told the BBC the allegations of harassment and torture of family members are false.
He said if the family had any fears from the police they could go to court to seek protection.
Ms Batool ends the video saying that "they are willing to co-operate with the UK authorities to fight their case in court".
At an inquest last month, the cause of death was said to be "not yet ascertained" but was likely to be "unnatural".
Sara was said to have sustained "multiple and extensive injuries", the post-mortem tests found.
Sara's mother and grandmother told Polish television they could not recognise Sara in the mortuary because of her extensive injuries.
According to Pakistan police, they were only informed about the international search for Mr Sharif, Ms Batool and Mr Malik five days after Sara's body was discovered on August 10.
The search for the trio remains ongoing.