RANCHO CORDOVA (CBS13) – A letter claiming to provide information about the notorious “East Area Rapist” case is being mailed to people living in Rancho Cordova – but police say it isn’t from them.

Officials say the letter is not entirely factual and is not from any law enforcement agency.

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Investigators fear it could do more harm than good.

“It’s important to note that there are victims out there still that are affected by this case,” said Shaun Hampton with the Sacramento County Sheriff’s Department.

Investigators want to remind people any new information from a law enforcement agency would be properly labeled.

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“We don’t want to take away from the legitimacy of those cases not the legitimacy of those that were victimized,” Hampton said.

February marks 40 years since Brian and Katie Maggiore were killed in the backyard of their Rancho Cordova home.

Investigators believe the pair stumbled upon the East Area Rapist. After a struggle, he shot them both dead and then took off.

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Anyone with information about this case should contact the Sacramento County Sheriff’s Department.