PHILADELPHIA - A Philadelphia college professor is defending tweeting that he was "trying not to vomit" after seeing a first-class passenger give up his seat to a soldier on a flight.

George Ciccariello-Maher, who teaches at Drexel University, tweeted Sunday: "Some guy gave up his first class seat for a uniformed soldier. People are thanking him. I'm trying not to vomit or yell about Mosul." Ciccariello-Maher's account is private, but screenshots of his tweet were shared by others.

Ciccariello-Maher wrote on Facebook Thursday that he respects soldiers, but doesn't respect U.S. actions in Iraq.

Drexel says in a statement that the professor's comments "do not represent the University's views."

Ciccariello-Maher also faced criticism in December for tweeting, "All I Want for Christmas is White Genocide," a post he said was satirical.