A father arrested over the horrific sexual assault of a young girl in a Blair Athol toilet has been released, and all charges dropped, less than 24 hours after he was taken into custody.

Police on Thursday confirmed they had wrongly arrested a 29-year-old man who was cleared of direct involvement through DNA testing.

Detectives then arrested a northern suburbs man, 32, who was remanded in custody.

Police have not said what led to the second man’s arrest but the fact he was charged so quickly indicates the pair are closely linked by DNA.

Special Crimes Investigation Branch detectives arrested the 29-year-old man at his home, just after 6pm on Wednesday.

He was charged with two counts of rape, aggravated indecent assault, gross indecency and unlawful detention.

media_camera The Blair Athol playground and toilet block where the crime was committed — and CCTV of the suspect in the vicinity.

The man was refused bail and was due to appear in the Adelaide Magistrates Court on Thursday when police announced that he had been unconditionally released and all charges withdrawn.

“It has now been established … that this man is not the offender in this matter after forensic evidence cleared him of direct involvement in the attack,” a police statement said.

“Forensic Science SA are undertaking urgent forensic examinations in this matter. It is expected that the results will not be known until (today).

“Police will continue to take action, where appropriate evidentiary thresholds are met, to ensure the protection of the public in cases such as this.”

The 32-year-old man is expected to appear in the Adelaide Magistrates Court next week after police bail was refused and he was charged on Thursday night.

He will face the same charges as those originally laid against the 29-year-old man.

The victim — a 10-year-old girl — was sexually assaulted at Blair Athol Reserve, Leslie Ave, between 5pm and 5.30pm on April 3 while soccer training was under way nearby.

Speaking after the arrest of the first man, Serious Crime Branch officer-in-charge Chief Superintendent Mark Wieszyk described the incident as “abhorrent” and said detectives had been inspired by the girl’s courage. The mother of the victim claims her daughter’s mouth and eyes were covered by tape and her hands bound behind her head during the horrific attack.

The girl told her mother that two young girls, aged about three to five, were with the man and called him “Dad”.

“(My daughter) said: ‘My mum is outside’. He said: ‘I don’t care if your mum is outside’,” the woman, who cannot be identified for legal reasons, told The Advertiser last week. The mother said her daughter was forced to the floor and told to “wash your hands” after the attack. She elbowed the man and ran from the toilets.

CCTV of Blair Athol sexual assault SA Police have released new CCTV showing the suspect going to and from the Blair Athol park.

Supt Wieszyk said there were almost 60 calls to Crime Stoppers about the incident.

“The victim has displayed incredible courage during this investigation, which has inspired detectives,” he said.

“Detectives actually did a lot of work, followed a lot of leads. They really wanted to do their part in coming to this result.”

Video captured by a household security camera adjacent to Blair Athol Reserve was released to the public last week and shows a man pushing a twin stroller carrying two small girls out of Blount St and across Leslie Ave.

The video shows the two girls with the man playing on the playground before the assault and then the three leaving the reserve quickly afterwards.