The Clark County Sheriff’s Office is seeing an increase in reports of phone scams and is warning residents against falling victim.Within the past two weeks, the agency has taken 15 reports of scams where the caller claims to work for the Internal Revenue Service, said Det. Jason Granneman. The scammer calls Clark County residents and claims they owe money to the IRS. Then the caller demands that the residents pay the agency back by calling a number with an 867 area code and punching in a five-digit code, which the scammer provides.“They sound very formal and they are believable,” Granneman said. That, he said, is worrisome. The federal agency, however, is “certainly not going to call and demand you make a payment over the phone,” he said.The scammer on the other end of the line is very demanding and uses scare tactics to intimidate people, Granneman said.A tip to determine if someone is trying to scam you, Granneman said, is to ask for the person’s name, badge number and the name of the caller’s supervisor.“Any government agency is going to provide that to you; it’s required by law,” Granneman said.Another tip is to hang up and call the agency yourself to see if the phone call is legitimate.