Jonathan Elwell, a Berks County man and brother to Gay Elwell, has been missing since April 17, according to police.
Authorities in Iowa -- where Elwell's rental car was found April 20 -- are seeking the public's help in finding him.
"The fact that the car is found out in Iowa is not normal, so obviously it's a very great concern," Judge Elwell told the Morning Call Tuesday. "And we have no idea why he would have gone there or what he was doing there."
The Iowa Department of Public Safety said Jonathan Elwell was last seen in his hometown of Shillington, Berks County on April 17. Three days later, his rental car, a white Volkswagen Jetta, showed up in Crawford County, Iowa.
"Information discovered during the investigation indicates Elwell was in the Quad Cities area," the department wrote in a news release. "Additional information indicates that Elwell was in the Carroll, Iowa area on Wednesday, April 18, 2012. He has not been seen since."
Police say he may have also been traveling by bicycle in Iowa, as he used a bike as his main form of transportation in Pennsylvania.
Elwell is 44 years old, six feet, two inches tall, balding, with blue eyes. Anyone who has information about his whereabouts is asked to call their local police, or contact the Crawford County, Iowa sheriff at (712) 263-2146.