The incident took place at around 11pm, but he wasn't taken into custody until the following morning. It shows Emelia grabbing Cherwinski, who has been in a relationship with his girlfriend for 11 years, by the collar and slamming him into the wall.
Trump has come under fire following the Helsinki talks for what many saw as his unsettling embrace of the Russian strongman - and his seeming disavowal of his own intelligence agencies and their assessment that Moscow meddled in the 2016 election.