Vandals attack luxury Florida home of Cecil the lion's killer

Vandals have spray-painted the words "Lion killer" on the Florida vacation home of an American trophy hunter who killed a much-beloved big cat in Zimbabwe last month.

American dentist Walter Palmer continues to lie low amid international outrage over his illegal hunt of Cecil the Lion, a well-known attraction among visitors to the Hwange National Park in Zimbabwe.

Officials said they are investigating who scrawled graffiti found Tuesday on the garage door of his home in the wealthy Gulf Coast community of Marco Island - one of Florida's most exclusive addresses.

A spokesman for the Collier County sheriff's department said vandals also scattered pickled pigs' feet at the entrance of the million dollar residence.

Palmer, an avid trophy hunter, has not been seen in public since a furore erupted over news that he had killed the famous lion, who was wearing a tracking collar as part of an Oxford University research project.

The wealthy American reportedly paid $US55,000 ($A74,525.75) for the hunt, in which Cecil was lured out of the park to be killed.

Through a lawyer, Palmer has apologised for killing the lion, saying he was misled by professional hunters in Zimbabwe who organised the expedition last month.