Penrith Panthers CEO Brian Fletcher has been subjected to a death threat at the club's office from a now deceased member of the public.

Fletcher arrived at work last week to a disturbing package which had arrived in the mail.

The Daily Telegraph are reporting that the package had a death threat note against Fletcher, as well as razor blades, used condoms and white powder.

Fletcher, who notified police and other members of the Penrith executive, remained home for a week while police investigated. They managed to locate the perpetrator, however, the alleged offender had committed suicide between the sending of the package and the investigation of police.

The Panthers' CEO has now returned to work with police confident any threat to Fletcher or the Panthers' organisation has passed.

Speaking to the publication, Fletcher said he also informed the NRL of the incident, and worked from home to not put anyone else at the Panthers in danger.

“The police took the envelope and went away, I had a week away from work and worked from home on advice,” he told the publication.

“I didn't want to put anyone else in danger in case it was something drastic. I was quite OK, I didn't go out that much.

“The envelope was addressed to Panthers so I felt comfortable that they didn't know my home address."

Police told Fletcher that the person who sent the letter had sent a number of other letters with similar contents to other high profile people around Sydney.

Fletcher is now back at work with the Panthers set to have a bye this weekend, before taking on the Parramatta Eels in a grand final rematch next weekend.