Police are working with international authorities to find the three people over the death in Woking.
A murder investigation has been launched after the body of a 10-year-old girl was discovered in Surrey.
She was found after police officers were called to an address in Hammond Road, Woking, at about 02:50 BST on Thursday following a safety concern.
Det Ch Insp Debbie White said it was “a devastating incident”.
Police had identified a number of individuals they would like to speak to and were not looking for anyone else, she said.
A spokesperson for the force said no-one else had been injured, and no arrests had been made.
A neighbour who lives directly opposite the house said a family with six children had lived at the property for less than six months.
“They were normal children, friendly. They seemed like a decent family,” he said.
“It doesn’t seem real.”
Image source, PA Media
On Thursday, Det Ch Insp White said: “Our officers are working hard to build a picture of what happened.
“We have no reason to believe there is any risk to the public.”
There was a significant police presence near the address in Hammond Road, which would remain closed over the coming days, she added.
The deceased girl’s family have been informed and are being supported by specially-trained officers.
Another neighbour, who wished to remain anonymous, described the area as a “pretty normal” neighbourhood, adding: “There is no real activity going on.”
Another local added: “The area is very peaceful. It is busy during term time with children walking to and from. But it’s a lovely, vibrant place normally.”
A spokesperson for St Mary’s Horsell in Woking said the church would be open so the community could attend for “prayer, reflection or comfort”.
“Our thoughts and prayers are with our whole community, but especially those who will be so deeply affected by this tragedy,” they said.
Follow BBC South East on Facebook, on Twitter, and on Instagram. Send your story ideas to southeasttoday@bbc.co.uk.
Sign up for our morning newsletter and get BBC News in your inbox.
