His desperate parents flew from their home in New Hyde Park to Chicago, where 18-year-old Harsha Maddula goes to school, to help with the search.
Maddula hasn't been seen since a party early Saturday morning.
The pre-med student is a sophomore at Northwestern University.
Police there were notified when he didn't show up for a meeting. By Monday, his parents called police themselves.
"I don't know after the party what happened to him, and nobody can find him and nobody can trace him," dad Prasad Maddula said. "I am still surprised why they cannot trace him."
Authorities say it is a frustrating search because there just isn't a lot of evidence.
There has been no activity on Maddula's cell phone, he didn't use his dorm key and he doesn't appear anywhere on surveillance video.
And even with that, his parents say there's no way he simply walked away.
"No, absolutely not, 200 percent sure," mom Dhannalakshmi Maddula said. "He just came Wednesday over here to help first year students. Classes start this Thursday, but he wants to help. He's a very helping boy and he's so good. I don't know what happened."
He was excited, his parents say, to help incoming freshman get acclimated to the campus.
He is described as studious and responsible. He is also diabetic.
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