Rick Anaya, chief executive of the council, said he had brought about 6,000 J-1 visa students to the United States this summer. Mr. Anaya said he had tried to respond to the Palmyra workers’ complaints. “We are not getting any cooperation,” he said. “We are trying to work with these kids. All this negativity is hurting an excellent program. We would go out of our way to help them, but it seems like someone is stirring them up out there.”

A spokesman for Hershey’s, Kirk Saville, said the chocolate company did not directly operate the Palmyra packing plant, which is managed by a company called Exel. A spokeswoman for Exel said it had found the student workers through another staffing company.

The spokeswoman, Lynn Anderson, said: “We contract with a staffing agency to provide temporary employees, some from the local work force and some J-1 visa holders. We don’t have a lot of influence over some of those issues that they’ve raised.”

A labor organization, the National Guestworker Alliance, which has been working with the students, presented a complaint on Wednesday to the State Department asking for the Council for Educational Travel, U.S.A. to be removed from its list of sponsoring organizations.

In the protest on Wednesday, about 200 students who were scheduled to start work on an evening shift at 3 p.m. walked into the plant and presented a petition with several hundred signatures to a management representative. Then, together with some students coming off the daytime shift, they marched out.