The birds, a male and a female, were found in a cardboard box in Wulfric Square in Bretton at around 6pm on Monday 1 November and were victims of intentional cruelty.
Each of the poor birds had both legs broken. A kind-hearted member of the public found them and took them to a nearby wildlife rehabilitator.
Sadly the injuries were so severe both birds had to be put to sleep to prevent them suffering any further.
The RSPCA was contacted and Inspector Justin Stubbs is investigating.
He said: “It is really upsetting to think that someone has done this to these innocent animals. They would have been in a tremendous amount of pain - and whoever did this then just left them in a box.
“Fortunately they were found by a kind member of the public who did their best to help them. Given the type of injuries and the fact they were found in a box the only real conclusion is that this was a case of intentional cruelty and not an accident.
“I am in the process of looking at CCTV in the area and I would ask anyone who may have any information to please contact me in confidence on the RSPCA inspectorate appeal line on 0300 123 8018.”
To help the RSPCA continue rescuing, rehabilitating and rehoming animals in desperate need of care please visit our website or call our donation line on 0300 123 8181.