NEW YORK — Police officers in helmets streamed into Columbia University early Wednesday evening to remove a group of mask-clad protesters who staged a Pro-Palestinian demonstration inside the school’s main library.

Videos shared on social media showed the long line of NYPD officers entering the library hours after dozens of protesters pushed their way past campus security officers, raced into the building, then hung Palestinian flags and other banners on bookshelves in an ornate reading room. Some protesters also appeared to have scrawled “Columbia will burn” across framed pictures.

Other videos showed campus security officers barring another group of protesters from entering the library, with both sides shoving to try to force the other group aside.

The university’s president, Claire Shipman, said in a statement Wednesday evening that the protesters who had holed up inside a library reading room were asked repeatedly to show identification and to leave, but they refused. The school then requested the NYPD come in “to assist,” she said.

— The Associated Press