Five AFL players from five different clubs have received death threats in letters sent to each club, with police taking the threats "extremely seriously".
The Nine Network last night revealed the threats on the AFL Footy Show, but did not name the players or clubs involved, although three of the clubs are believed to be Victorian.
Victoria Police spokesman Adam West has confirmed an investigation into the threats are underway.
"Moonee Valley criminal investigation unit detectives are investigating a series of threatening letters allegedly sent to a number of AFL players," West told News Ltd.
"Victoria Police takes threats made against any person extremely seriously and is currently investigating these matters."