“Investigators were interviewing everybody. Here we were in Mason City — and people go away forever? That’s not supposed to happen.”

Leads of any substance were few.

Neighbors at the apartments might have heard her scream; there was a report of a white van seen in the parking lot that morning.

At first the search was conducted in an area around the Key Apartments. Soon the perimeter widened over and over again, spiraling out as more hands became involved.

“Those first weeks we had FBI, DCI — not just investigators; we had teams of investigators,” Stearns said.

In just two days 30 people were interviewed by 15 investigators, according to Globe Gazette accounts.

An ABC-TV program on the 10th anniversary of her disappearance reported Huisentruit had spotted a van following her in October 1994, giving rise to speculation that a stalker was at work.

“But it never happened again, Stearns said. “We don’t rule anything out, but I really don’t think this is a case of stalking.”

A man Huisentruit was seeing socially at the time, John Vansice, remains “a person of interest,” said Stearns.