“Obviously if that occurred, that would be very serious, and I agree that that would be an illegal act,” Representative Mike Turner, Republican of Ohio and a former chairman of the Intelligence Committee, said on “Face the Nation” on CBS.

Senator Tim Kaine, Democrat of Virginia, said on CBS that if the report was accurate, the attack “rises to the level of a war crime.” And on CNN, when asked if he believed a second strike to kill survivors constituted a war crime, Senator Mark Kelly, Democrat of Arizona, answered, “It seems to.”