01/12/2018 10:03 EST | Updated 01/12/2018 10:20 EST

RCMP investigate after sexually offensive material mailed to man for 3 years

RED DEER, Alta. — Why would people in central Alberta anonymously mail sexually offensive material to someone they do not know?

That is a question Red Deer RCMP are trying to answer as they try to identify the suspects.

Mounties say they are investigating after a man received the offensive material every December for the past three years.

Police say they have surveillance camera images of two suspects — a man and a woman — mailing the material at a grocery store post office on Dec. 8.

The man who received the mail says he doesn't know either of the suspects or why he would be targeted.

RCMP say the suspects may have mailed similar material to other people as well.

"The action of repeatedly mailing offensive material to someone falls under the Criminal Code definition of criminal harassment," RCMP said Friday in a release.

Police are asking people with information to contact Red Deer RCMP and say if a tip leads to an arrest, there could be a cash reward.