Police were called on Tuesday night to stop demonstrators projecting slogans on to the side of a library at George Washington University.
The college said the protest had violated its policy and caused “distress” to some students.
One of the messages beamed on to the building in Washington DC said, “Free Palestine from the river to the sea”.
Other messages projected in big white letters on to the Gelman Library included “End the siege on Gaza” and “Divest from Zionist genocide now”.
“Glory to our martyrs” was another phrase that appeared. Demonstrators told the college newspaper, the GW Hatchet that this slogan referred to any Palestinian killed by Israel, and not Hamas gunmen.
StopAntisemitism, an antisemitism watchdog, called on the university to expel the students involved.
“Demonstrations like this cloak themselves in politics to evade responsibility for what they really are: celebrations of murder,” said its director, Liora Rez, in a statement to the BBC.
The university said in a statement on Wednesday that the unauthorised protest had violated its policy.
“The statements made by these individuals in no way reflect the views of the university,” said the college.
“We are reviewing this incident and will take any appropriate steps with respect to the individuals involved in accordance with university policies.
“We recognize the distress, hurt, and pain this has caused for many members of our community.”
According to the GW Hatchet, university aides and two campus police officers asked four members of Students for Justice in Palestine to stop the protest, which lasted about two hours.
Students for Justice in Palestine did not immediately respond to a BBC request for comment.
But a spokesperson for the group told the Hachet newspaper: “I feel very frustrated with how the university has responded.
“They have consistently shown that they do not respect our lives. They do not respect our right to free speech.”