Investigators say they have obtained security footage from the night a severed pig’s head was left at the front entrance to the Montreal Police Brotherhood.

The pig’s head was found outside the offices of the Montreal Police Brotherhood early Friday in what police suspect was a move to grab attention.

“It’s a direct threat to the police service, to police officers,” Cmdr. Ian Lafreniere told CTV News Channel. “That’s why we’re taking that very seriously.”

The head was found at the centre of a star-shaped pentagram drawn in chalk outside the union office on Gilford Street in Montreal.

A note was also found pinned to an arrangement of branches leaning against the door. The translation from French read: “You have taken them alive! We want them back alive! May ghosts haunt you forever!”

Lafreniere said the note included the names of missing people.

It also included a pentagram image and a drawing of an eye inside a wide diamond.

He added that the branches were arranged to resemble a body with no head.

Lafreniere says the incident comes just two days before an annual anti-police brutality protest in Montreal. He said there is no direct link to the protest, but there have been anti-police crimes in the past ahead of the event.

“We’re looking for a very complicated explanation for something that could be as simple as to do some publicity before a protest,” he said.

Forensic teams are investigating.