Sara Sharif's father, stepmother and uncle have been arrested on suspicion of murder in connection with the death of the 10-year-old girl.
In a statement, Surrey Police detective superintendent Mark Chapman said:
"Two men, aged 41 years and 28 years, and a woman, aged 29 years, were arrested on suspicion of murder after disembarking a flight from Dubai.
"They are currently in custody and will be interviewed in due course."
After being arrested they were taken to Guildford police station.
The three arrived at Gatwick airport just after 7.30pm on an Emirates flight from Pakistan, via Dubai.
A passenger on the flight told Sky News that police officers boarded the plane as soon as it landed and arrested the three suspects, who remained calm and complied with the officers' instructions.
The passenger said the suspects were taken off the flight before anyone else.
The passenger told Sky News that police questioned a few people who had been sitting around the suspects on the plane, asking if they had tried to speak to them during the flight.
Officers also said that nobody was allowed to film.
The girl's father Urfan Sharif, stepmother Beinash Batool and uncle Faisal Malik are believed to have travelled to Pakistan on 9 August and were being searched for by police in the country.
Sara was found dead at her home in Woking, Surrey, on 10 August after a man identifying himself as her father called 999 from Pakistan.
Mr Chapman said Sara's mother had been informed of the arrests.
"Our thoughts remain with her and those affected by Sara's death at this very difficult time," he added.
"This has been an extremely fast-moving, challenging and complex enquiry and we remain absolutely committed to conducting a thorough investigation into Sara's death.
"We will not be commenting any further at this point and will provide further updates as and when we are able to."
In a video shared last week with Sky News, Ms Batool described Sara's death as an "incident".
(c) Sky News 2023: Sara Sharif's father, stepmother and uncle arrested on suspicion of murder