Four peregrine falcons which had been nesting at Glenwherry near Ballymena are believed to have been killed, police have said.
The two adult and two chick Peregrine Falcons went missing from the area on the Glenhead Road.
One of the chicks was later discovered fatally injured and it is believed it may have been shot.
The other birds are also thought to have been killed. Police have said they are treating it as animal cruelty.
They added that the falcons are a protected species.
Police investigations are continuing and they want anyone with information to contact them on 0845 600 8000
BBC