A lecturer at the University of Manchester Institute of Science and Technology could have sustained permanent eye damage after a student used a laser pointer during a lecture.
The university said three similar incidents occurred in the same week earlier this month.
"Such irresponsible behaviour will not be tolerated," said a spokesman. "The use of laser pointers in this way is a serious disciplinary offence and in some circumstances could constitute a criminal offence."
The damaging effects of such devices vary, depending on the power output, length of exposure and lighting conditions or pupil aperture. One lecturer is being monitored at an eye hospital for long-term damage.