There was controversy in Buenos Aires this evening, when delegates leaving the G20 Summit were surprised by a protestor who threw a mate tea bag at US President, Donald Trump, hitting him on the forehead.
Police moved in, and a woman was led away for questioning.
Mate is a traditional South American caffeine-rich drink made with the dried leaves of the yerba mate. It is infused in hot water, and sipped like tea.
The drink originated with the Guarani, and was also popular with the Tupi people before it spread to other South American countries - Argentina, Uruguay, Paraguay, and parts of Bolivia, Chile and Brazil - as well as Syria and Lebanon, which are not in South America.
Police later charged the woman with 'wasting a tea bag'.