Oregon Attorney General Ellen Rosenblum is warning consumers to avoid returning unknown phone calls.

Consumers have reported waves of “One Ring” or “Wangiri” scam robocalls targeting specific area codes in bursts, often calling multiple times in the middle of the night. These calls are likely trying to prompt you to call the number back, often resulting in per minute toll charges similar to a 900 number.

Recent reports indicate these calls are using the “222” country code of the West African nation of Mauritania.

Of course, robocallers can spoof their phone numbers to make them appear as if they’re coming from anywhere in the U.S. or overseas. “If you receive a call from a phone number you don’t recognize, do not call this number back,” says Attorney General Rosenblum.

Advances in technology allow massive amounts of calls to be made cheaply and easily. In addition, spoofing tools make it easy for scammers to mask their identity. The Oregon Department of Justice is working to combat scam calls with consumer education like this Just Hang Up poster available for free online at https://www.doj.state.or.us/wp-content/uploads/2017/06/just_hang_up_poster.pdf.

If you think you have fallen victim to a One Ring scam, contact the Oregon Department of Justice online at www.oregonconsumer.gov or call 1-877-877-9392.