WASHINGTON, D.C.: A tarmac tiff between US and Chinese officials as President Barack Obama arrived in the city of Hangzhou prompted the posting — and prompt deleting — of an uncharacteristically sarcastic tweet by a US spy agency. “Classy as always China,” read the Defense Intelligence Agency (DIA) tweet, which linked to a New York Times article about the incident. The post was quickly deleted but not before the Wall Street Journal noticed the snark. The agency later tweeted its apology: “Earlier today, a tweet regarding a news article was mistakenly posted from this account & does not represent the views of the DIA. We apologize.” The tarmac kerfuffle included a shouting match that broke out as White House staffers tried to help American reporters position themselves to film Obama’s arrival in the eastern Chinese city for a G20 summit. “This is our country!” a Chinese official in a dark suit shouted at a White House staffer. “This is our airport!” The outburst was caught on camera, in an awkward prelude to face-to-face talks between Chinese President Xi Jinping and his American guest.