Residents in a Tempe neighborhood received letters in their mailboxes on Saturday that contained black-and-white images of child pornography, police said.

Each letter contained an identical photocopy with eight child-pornography images that were distributed to at least nine homes in the Maple-Ash neighborhood near the Arizona State University campus, police said.

Investigators collected several opened and unopened letters from different addresses, police said.

Sgt. Ron Elcock, a Tempe police spokesman, said some people may have made copies or distributed the images electronically in trying to warn other residents in the area.

But, he said, those people may have inadvertently committed thefelony of sexual exploitation of a minor, which is the legal term used to refer to child pornography.

"It is our recommendation to immediately delete whatever images they may have as they are considered contraband, and therefore are illegal to possess and/or distribute," Elcock said in a news release.

He also said there is no indication a child is in immediate danger.

Investigators ask that if residents continue to receive images to please contact the Tempe Police Department so they can continue to investigate who the sender is.

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