King Charles, the royal who is known for his activism for environmental causes, has allegedly been endangering multiple protected species of birds found in the UK.

According to a detailed report published by the Guardian, the monarch’s private estate at Sandringham in Norfolk has been linked to the deaths and disappearances of a string of legally protected birds over the past two decades.

In the documents obtained by the outlet revealed that the rural police have been investigating 18 cases of birds of prey found shot or poisoned, or which have gone missing in that time period.

One of the cases include the death of the last breeding female Montagu’s harrier named Sally, an already critically-endangered species with just nine left in the UK. She was the female in the last surviving breeding pair of Montagu’s harriers in the east of England. There are no longer any breeding pairs in the UK.

Cases mentioned in the files also include an occasion in 2007 when a young Prince Harry and a friend were questioned over the deaths of two hen harriers allegedly killed.

Katie-Jo Luxton, the RSPB’s director of conservation, said: “The UK has an ongoing problem with bird of prey persecution, and the majority of cases occur in connection with land managed for game bird shooting. The incidents we know of are just the tip of the iceberg and this is reflected in the fact that some species remain suspiciously absent from places they should thrive.”

“We need our governments to take these crimes seriously and help ensure better enforcement of existing laws, as well as bringing in essential new legislation such as the licensing of grouse moors.”

The only prosecution was in 2006 when a gamekeeper was fined for entrapping a tawny owl.