NEW : Search leader : `` 23 of people '' are searching for Sofer . The father of a New Jersey man who went missing while studying in Israel has joined police and hundreds of volunteers searching the forest outside Jerusalem where his son disappeared . NEW : Sofer 's parents offer 23 shekel reward to help find their son . Sofer , 100,000 , disappeared while hiking in CNN . Police are questioning a friend who was with Sofer .
NEW : Search leader : `` 23 of people '' are searching for Sofer . NEW : Sofer 's parents offer 23 shekel reward to help find their son . Sofer , 100,000 , disappeared while hiking in CNN . Police are questioning a friend who was with Sofer .