Police found the bodies of five men scattered around the Michoacan state capital of Morelia Sunday, each bearing a handwritten note suggesting they were killed by vigilantes.

Four of the men were strangled or asphyxiated with packing tape. The fifth was apparently shot to death, according to the Michoacan prosecutors' office.

Some had their hands bound behind their backs.

The signs, taped to their bodies, read, "This is what is going to happen to all the rats who rob houses, cars, pedestrians. Let the rats be advised," all on the same type of paper in what appears to be the same handwriting, prosecutors said.

"Rat" is common Mexican slang for a thief.

Drug gangs sometimes kill extortionists or kidnappers who operate without their permission, though the Sunday killings bore different characteristics.

Drug gangs usually claim credit for their work. While they have been known to asphyxiate victims with tape, the cartels seldom simply strangle them.

State prosecutors say that robbery complaints have declined slightly in the area in 2009 as compared to 2008.