MANHATTAN, New York (WABC) -- Some pro-Palestinian demonstrators say they were targeted by apparent stink bomb at Columbia University Friday.
The demonstrators say they were attacked with what they believe to have been a "chemical-based weapon" during a gathering in support of Palestinians amid the ongoing Israel-Hamas war.
Investigators have recovered clothing from three of the six people who say they were exposed, and the forensics lab is attempting to determine what, if anything, the articles of clothing can be tested for.
Additionally, the NYPD has recovered surveillance video of two people spraying an unknown substance on a light pole before the pro-Palestinian rally.
Columbia University has provided detectives with the names of "alleged perpetrators" who they have reason to believe sprayed a foul-smelling chemical during the rally. The two have been banned from campus.
At this point, the investigation does not fall within the parameters of a hate crime investigation, instead the incident is being investigated as a possible assault.
The NYPD told ABC News that protesters said they smelled a foul odor and began to feel nauseated, accompanied by headaches, during the demonstration. The victims refused medical attention at the scene, police say.
"We condemn in the strongest possible terms any threats or acts of violence directed toward anyone in our community. The University is committed to taking urgent action with the appropriate authorities in any such cases. The safety of every single member of this community is paramount," Interim Columbia Provost Dennis Mitchell said in a letter to the university community.
No arrests have been made.
ABC News contributed to this report.