The boy was rushed to hospital after the incident in the River Tay in Perthshire.
Medics desperately tried to save the boy’s life following the harrowing scenes in the river near Stanley village.
But police have since confirmed the boy tragically died in the early hours of this morning.
In a statement, Police Scotland said: “Police Scotland can confirm that sadly the 12 year old who got into difficulties in the River Tay near Stanley on Sunday has died in hospital in the early hours of this morning.
“Our thoughts are with his family and friends at this very tragic time.
“Enquiries into the incident are ongoing and a report will be submitted to the Procurator Fiscal”.
The tragic incident comes after a number of water-related fatalities across the country this month.
On July 23, the body of a man was pulled from the water at Cotswold Water Park near Cirencester shortly before 8.50pm.
The man had reportedly jumped into the lake while looking for his missing dog.
A spokesperson said the man was pronounced dead at the scene and the coroner and the man’s next of kin had been informed.
A director of one of the lakes at the park said: “We have assisted our neighbours at the Country Park and Beach to carry out a search in the lake, for a person.
“The person has gone in – they have been looking for – trying to find their dog.”
In London, a missing man was also pulled from the River Thames in the Kingston area on July 24.
The man, believed to be aged 47, was reported to have entered the water from the riverside and began swimming, but did not resurface.
A body, believed to be the same man, was recovered at 4.30pm.
Just a day before police recovered the body of a 23-year-old man who had entered the water at Shadwell Basin in East London.
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