Published: Oct 25, 2011 5:16 PM EDT

DALLAS (AP) - A national black sorority is warning alumnae in the Dallas area to remove items linking them to the group after authorities say it appears a rapist is targeting members.
    
Delta Sigma Theta Sorority Inc. is advising members to remove anything identifying them as members from their cars, homes and offices. Also, the sorority warned members not to wear clothing or accessories identifying them as members and to remove personal information from social networking sites.
    
The sorority said it has been notified of a series of four sexual assaults. Law enforcement officials say the victims are all black females in their mid-50s to mid-60s and are associated with the same sorority.
    
Law enforcement officials say that during the assaults, the suspect indicated he knew information about them.

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