Shannon Tudor, president of Miami Valley Crime Stoppers, stressed that people can remain anonymous while submitting tips.
“When they submit a tip they’re given a number and we don’t even know who they are,” she said.
Johns previously called Chapman’s disappearance “very suspicious” and “a well-orchestrated event.”
“So we know that people know,” he said Friday. “What we need now is people to come forward and step up and do the right thing and let us know where she is and what happened to her.”
Chapman was last seen early Dec. 27 at an Autumn Woods Drive apartment in Trotwood. Her sister reported her missing two days later.
On Jan. 6, Chapman’s SUV was found in Middletown with her purse and other personal items. The 30-year-old does not have ties to the Middletown area, and Johns said it was not clear why she’d be in that area.
In the two months since her disappearance, police have searched the area between Dayton and Middletown, as well as other locations throughout the region.
On Feb. 11, approximately 30 to 40 Dayton officers and EquuSearch volunteers participated in a large search for Chapman, using drones, ATVs, canine units and other equipment.
Johns explained that tips can help investigators determine where to search next. By increasing the reward, he hopes it will help police get new information.
“We’re still trying,” he said. “I think this to effort in increase the reward to $20,000 is a step in the right direction.”