The "Primetime Live (search)" report examines how close those interns were able to get to the reactors, theorizing the facilities could be vulnerable to terrorists who could set off bombs that release radiation into the atmosphere.
ABC said its interns found unlocked doors, saw unmanned security booths and, in some cases, were given guided tours that gave them access to control rooms and reactor pools.
Officials at Kansas State and Ohio State universities expressed anger about the report before its scheduled airing Thursday.
"We are concerned that interns, college students, were placed in a position where they were dishonest about their roles and intentions," Terry King, dean of Kansas State's engineering school, said in a letter.
ABC said its interns were instructed not to lie.
Two students each from Columbia, Northwestern, Harvard, Southern California and California-Berkeley universities were working at ABC News as part of an internship program financed by the Carnegie Corp. and the Knight Foundation. They were assigned to the project and supervised by reporter Brian Ross and his investigative team — and were picked, in part, because looked the part.
"The day has long since passed that I could pass as a college student," said Ross, 56.
They were told to go to the reactor facilities, say they were graduate students interested in nuclear power, and ask if they could look around. They carried regular cameras, not TV cameras, and did not say they were from ABC News. They weren't being untruthful, Ross said.
Ohio State and Kansas State officials say they give tours because, as educational facilities, it's their job to spread the word about how nuclear energy is being used.
Saying the interns were able to get close to the facility is "like coming to my driveway and saying, `Guess what? I just got into McDonald's!'" said Earle Holland, Ohio State senior director for research communications.
At Ohio State, security procedures were correctly followed, and the interns had their bags searched and held during the tour. The tour was ended because one of the interns attempted to take a placard that listed security precautions in case of a bomb scare, he said.
At Kansas State, officials anticipated the visit; word had gotten around the small nuclear research community that reporters saying they were students had approached facilities. The students were given a tour anyway, even though this was later cited by ABC an example of a potential security risk.
The interns flirted with security officers to try to get in, said Ken Shultis, Kansas State's nuclear energy program director. The guards flirted back, since they were trying to get the interns to pose for a picture they wanted to provide to the FBI.
Both university officials said the interns should have identified themselves as being from ABC News.
"I think the ethics is somewhat questionable," Shultis said. "It's a fine point when they were trying to misdirect or mislead."
But ABC said it's likely they would have been treated differently as reporters. The point was to show how a terrorist could pose as a student and easily be a threat, Ross said.
"We were students," said Dana Hughes, a Columbia University Graduate School of Journalism student who worked on the project. "We were interested in the programs. We did not hide our cameras. We were hiding in plain sight. It wasn't as sneaky as they were making it out to be."
If all it took to get into facilities was talking like a student or flirting, "some people could find that a questionable line of defense," she said.
Alex Jones, director of the Joan Shorenstein Center on the Press, Politics and Public Policy at Harvard, which provided two of the interns, said he didn't want to prejudge ABC's report.
"I don't think there's anything wrong with finding out whether minimal security was being observed at nuclear facilities, providing you didn't misrepresent yourself," he said. "And from what I understand, none of these students did."
Ross said it wasn't a case of the interns being taught "gotcha" journalism instead of investigative journalism. The students did a great deal of research into the nuclear programs before going to the universities, he said.
The students didn't embark on the project with a specific result in mind. "A lot of them were hoping that they didn't find these stories," he said.
Two of the students have subsequently gotten jobs at ABC News and Ross said he hoped the network would hire more.