Sara was found dead on 10 August, with a post-mortem revealing she had "suffered multiple and extensive injuries", which were "likely to have been caused over a sustained and extended period of time".

Police in the UK have identified her father, Urfan Sharif, his partner, Beinash Batool, and Mr Sharif's brother, Faisal Shahzad Malik, as people they want to speak to as part of a murder investigation.

On Sunday, Surrey County Council said Sara was known to the authority before her death.

"We cannot comment further while the Surrey Safeguarding Children Partnership's thorough review process is ongoing," a spokesperson for the authority said.

The council said it was "working tirelessly with our safeguarding partners to gain a full understanding of the situation as quickly as possible".

On Friday, council leader Tim Oliver said: "This is an incredibly sad situation and our thoughts and deepest condolences are with everyone affected."

He said the national Child Safeguarding panel had been notified of the death and a multi-agency rapid review was under way, in line with standard process following the death of a child.

He explained: "This rapid review will determine whether a local child safeguarding practice review (LCSPR) is to be undertaken by the Surrey Safeguarding Children Partnership.

"An LCSPR is a statutory process, bringing together partners including the police, health, social care and education to review practice of all agencies involved, organisational structures and learning."

It comes after police in eastern Pakistan said they were seeking to arrest Mr Sharif in connection with Sara's death.

Read more:
Police in Pakistan seeking to arrest Sara's father
Trio booked flights to Pakistan a day before body found

According to authorities, Mr Sharif travelled to Pakistan's capital, Islamabad, with Ms Batool and Mr Malik on 9 August - the day before Sara's body was found.

Mr Sharif's family home is in Jhelum, Punjab, around 84 miles from the capital.

Officer Imran Ahmed said police found evidence that Mr Sharif briefly returned to Jhelum, before leaving and going into hiding.

Another officer in Jhelum, Nisar Ahmed, said he and his men visited the village of Kari - where Mr Sharif was born - but learned the family left around 20 years ago and never returned.

There is no formal extradition treaty between the UK and Pakistan.

However, Pakistan has transferred people to the UK in the past, including Piran Ditta Khan, who was extradited to the UK in April in connection with the 2005 killing of PC Sharon Beshenivsky.

The cause of Sara's death is "still to be established".

According to UK police, Mr Sharif called 999 from Islamabad on 10 August, expressing a concern for his eldest daughter's safety - although the exact details of the conversation are unknown.

Sky News has seen the passports and holding plane tickets for Mr Sharif, Ms Batool and Mr Malik.

Eight tickets in total were booked by Sara's father.

These were for three adults and five children - and paid for by his brother Mr Malik at a cost of around £5,100, according to a travel agent that sold the tickets.

Officers from Surrey Police have remained at the family's property in Hammond Road in Horsell, a village less than a mile north of Woking town centre.