Nabeeha, pictured second from left, was killed by the kidnappers
Nigerian police had no role in rescuing four sisters and their cousin from kidnappers, an uncle of the girls has told the BBC.
They were taken from their home in Abuja earlier this month, along with another sister who was later killed.
The uncle said a ransom was paid and the kidnappers dropped the girls in a forest for them to be collected.
On Sunday, police said they had "successfully rescued the victims", reuniting them with relatives.
Sheriff Al-Kadriyar, the girls' uncle, said the family went to collect them after a ransom was paid.
"There's nothing like rescue on this matter, we paid ransom - even though I can't disclose how much for security reasons," he told BBC Yoruba.
The Nigerian police spokesperson has not responded to a BBC request for comment.
The case has shocked the country, with people donating to a crowdfunding initiative to help raise the money.
In total five sisters were taken hostage in the Abuja suburb of Bwari on 2 January, along with their father Mansoor Al-Kadriyar, who was later released to raise the ransom.
Sheriff Kadriyar clarified that contrary to earlier reports that six Al-Kadriyar sisters had been abducted, one of the girls was in fact their cousin who had been staying with them over the school holidays.
Twenty-one-year-old Nabeeha, a final-year university student, was killed a few days after her father's release as a warning that the ransom of $68,000 (£53,000) must be paid.
Nigeria's defence minister had urged the family not to pay the ransom, but the Al-Kadriyars said they had no choice.
A controversial law that criminalises ransom payments was passed in 2022 aimed at tackling the country's spiralling and lucrative kidnapping industry.It carries a jail sentence of at least 15 years for anyone who pays a ransom, however no-one has been arrested, and a former minister is among those who said he had helped organise the payment to the kidnappers of the Al-Kadriyar sisters.
Sheriff Kadriyar, who said he was involved in negotiating with the kidnappers, explained that the money had been handed over to them on Wednesday.
His account backs up two others given by relatives to Nigeria's Daily Trust newspaper.
They all say that the girls were released on Saturday. One of them then called the family in the early evening, giving their location.
"The kidnappers chose the day and the location we were to pick up the girls about four or five days after ransom payment," the uncle said.
A group of male relatives then headed to the Kajuru Forest in neighbouring Kaduna state to find them. Along the way they chanced upon an army unit and requested help.
These army officers escorted them to find the girls - afterwards taking them all home by around 23:30 local time (22:30 GMT).
"We are happy and we thank God that the girls were found alive," the uncle said.
His brother and nieces were now being treated at a medical facility, he said.
Kidnapping has become rife in Nigeria, with hundreds of people abducted in recent years, largely by criminal gangs who see it as an easy way to make money. It has been particularly bad in the north-west of the country.
There has been an outcry that the insecurity has reached the capital, prompting Abuja's police force to launch a special squad to tackle the kidnapping gangs last week.
The family did not want to discredit the police but wanted to make it clear how they had managed to free the girls, Sheriff Kadriyar said.
By Mansur Abubakar, BBC
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