Sofer was reported missing on Friday after his friend and hiking companion "lost contact" with Sofer in the forest outside Jerusalem.
The circumstances of Sofer's disappearance are a mystery, Rosenfeld acknowledged. "It is not clear if the disappearance was personal [or a] kidnapping. It's not clear at all."
Sofer's parents landed in Israel on Monday. Family spokesman Dov Hirth said the Sofers are frustrated by the slow pace of the search. "A physically, mentally and emotionally healthy young man does not go missing for 72 hours," adding, "The family is not satisfied with the way the search and rescue operation has been handled thus far."
The missing man's family has requested the Israel Defense Forces assist the search, citing a recent murder in the forest of 16-year-old Palestinian teen Mohammed Abu Khediar by Jewish assailants "and especially the ongoing tensions with Palestinians."
On Monday, the website Jewish Political News and Updates reported a possible lead in the search efforts after police and K9 dogs located belongings believed to be Sofer's in the forest.