The mother of a 12-year-old girl who drowned has claimed institutional racism within the police means the family may never know how she died.
Shukri Abdi drowned in the River Irwell in Bury, in Greater Manchester, on 27 June.
The family claim officers failed to carry out a full investigation and treated them differently because of their ethnic background.
The Independent Office for Police Conduct (IOPC) is investigating.
Greater Manchester Police (GMP) previously said the death was a "tragic incident" and it did not believe there were any suspicious circumstances.
It has now told the BBC it is "still investigating on behalf of the coroner".
Police 'not sympathetic'
Shukri's mother, Zam Zam Ture, told the BBC's Victoria Derbyshire programme that when she reported her daughter missing on the day of her death, police initially failed to act.
Approximately 10 hours later, she said, she was informed that her daughter had been found dead, but described police as "not sympathetic".
She said they spoke to her "harshly" and were "trying to convince [her] that her daughter had been swimming", which the family say was unlikely as Shukri could not swim, had been wearing full Islamic dress and it would have been "out of character" for her to attempt to do so.
The family's lawyer Attiq Malik said "within hours" of Shukri's death, GMP had published a press release saying there were no suspicious circumstances.
He said this had left insufficient time to check all evidence trails and discount other possibilities.
"The family's firm position is they have only been treated in that way because of their race, and had it been a different racial background more sensitivity would have been given, more investigation would have been done," he said.
Institutional racism, he claimed, meant officers had acted in such a way without "even realising it".
Their claims are now being investigated by the police watchdog, the IOPC.
The IOPC said: "We treat complaints of this nature with the utmost seriousness, and I know GMP share the view that the IOPC has a responsibility to examine the actions of the force after Shukri was reported missing - not least for public confidence."
Ms Ture said her daughter had been unhappy at school prior to her death.
She said she had personally reported instances of bullying to Broad Oak Sports College in Bury "many times".
The school produced a report for the family, but Mr Malik said it "essentially just said that they were not aware of any bullying".
He said the school failed to interview Shukri's mother for the report, despite promises, which he suggested showed they did not "fully investigate".
In a statement, head teacher Paul Greenhalgh said the school was "deeply saddened to receive news of Shukri's tragic death".
"We are currently working with Shukri's family in respect of any concerns which have been raised about the school [and] will be reviewing all policies and procedures at the school," he added.
"In particular, we will focus on the school's anti-bullying policy and procedures and other policies relating to the welfare of children."