Suspicious Activity 1947145131.rsc.cdn77.org

I typed "news" in my Safari browser search bar and it returned a Safari pop-up warning From "http://1947145131.rsc.cdn77.org": saying that Your system has detected possible Suspicious Activity. Please call the toll-free number below for a Microsoft-Certified technician to help you resolve the issue: 888-725-2042

For your safety, please do not open internet browser to avoid data corruption to the registry of your operating system..........

I assume this is a scam, but I am afraid to do anything until I hear from someone here at support.