Everton are in search of a new manager after Carlo Ancelotti left the club for Real Madrid at the end of the 2020/2021 season.
Benitez is currently unattached, having left his role as manager of Chinese Super League side Dalian Professional earlier this year.
The 61-year-old previously spent six years in charge Everton’s Merseyside rivals Liverpool, winning the UEFA Champions League and FA Cup with the Reds but he irked the Toffees supporters in 2007 when he described the Goodison Park outfit as a ‘small club’.
That description has not gone down well with Everton fans, and with Benitez the clear favorite to take over the club, most of them are against his appointment.
A banner with the message ‘We know where you live, don’t sign’ has been spotted close to Benitez’s home in Wirral and Merseyside police have launched an investigation to find out who is behind it.
A Merseyside Police statement said: "We can confirm police are investigating reports of a threatening banner at a location in Caldy today, Monday 28 June.
"At around 7am, it was reported that a banner made from bed sheets had been placed over a wall and bushes on a residential driveway, with wording which is thought to target football manager Rafa Benitez."
Detective Inspector Darren Taylor added: "This message has understandably caused some distress and worry for residents in the area. Due to the football language used, we suspect that it was aimed at Rafa Benitez - but whoever placed the message left it outside the wrong house.
"If anyone has information about who produced the banner or helped to put it up, please let us know as soon as possible."