Two swans have died after 12 were shot near to Windsor Castle in the UK.
The protected birds were hit with an air weapon and slingshot during two incidents last week in Barry Avenue in Windsor, Berkshire, Thames Valley Police said.
Four of the swans were found by police officers on January 24th, and a further eight were injured on Friday, the force added.
Two of the swans have since died and several are in a critical condition.
Wendy Hermon, operations director at charity Swan Support which cared for the injured birds, said she believed the perpetrators were "a group of people doing it for fun".
She said: "We've been doing this over 20 years and we've been dealing with everything you could imagine... but this is the worst in over 20 years that I've had to deal with in one hit with so many that have been deliberately shot.
"We've had one or two or maybe three but not all at the same time, but to get 12 within four or five days it's just so upsetting."
Ms Hermon added: "What are people doing? One is bad enough, but why are they keeping on? What are they trying to do - are they getting a buzz from it?"
Investigating officer PC Les Jones, based at Windsor police station, said: "These are very distressing incidents in which defenceless animals have clearly been targeted.
"Two of these animals have been killed and several others have been left severely injured.
"I understand that these incidents are very upsetting for people and we are carrying out an investigation in order to locate those responsible."