Authorities in southwest Florida revealed Wednesday that the vacation home of Walter Palmer, the Minnesota dentist who killed Cecil the lion, was vandalized with the words "Lion Killer" spray-painted on his garage door.

The vandalization was reported Tuesday morning, according to the Guardian. However, authorities have been unable to determine when it occurred.

In addition to the spray painting, Walter Zalisko, owner of Global Investigative Group, a private firm hired to protect the property, reported that vandals allegedly left pickled pig feet in the driveway.

Marco Island police could not confirm the information about the pig feet, which was also reported and photographed by local media. Authorities have started an investigation regarding the matter, according to the Chicago Tribune.

Since killing Cecil, Palmer, 55, has received threats — some even threatening to kill him — on social media. Protests have also been held outside his Minnesota office, and a handmade sign criticizing him was left in his yard last week.

Zalisko revealed security cameras were being installed to further supervise and protect his property, according to Reuters. Palmer purchased the home for $1.1 million in 2013 property records show.