HONG KONG — Four American instructors from a small Iowa college were injured in a stabbing attack while on a teaching trip to China, their school and U.S. officials said.

The four instructors from Cornell College, a private liberal arts college in Mount Vernon, Iowa, were injured “in a serious incident” during a daytime visit to a public park, the school’s president, Jonathan Brand, confirmed in a statement.

They were accompanied by a faculty member from the school’s Chinese partner…