President Donald Trump was booed for the second time in a week at a sporting event on Saturday as he watched mixed martial artists brawl in a cage in New York.Trump sat around 15 feet away as UFC fighters delivered vicious kicks and punches to the face and body of their opponents, regularly drawing blood, at Madison Square Garden.The president was seen clapping and at one point stood up for a better view as 20 000 pumped-up fans screamed and swore amid an electric atmosphere at the pay-per-view spectacle.Jeers rang out as Trump, wearing a dark suit and red tie, punched his fist and waved at the crowd as he walked into the arena shortly before 22:00.Many fans also cheered the US leader and there was no repeat of the loud chants of "lock him up" that greeted his appearance at a World Series baseball game last weekend."We'd be having more fun if he wasn't here," 50-year-old Anna Torres, who booed loudly with her boyfriend, told AFP.Some spectators, however, were delighted to see the president, who has a fight of his own on his hands back in Washington with the Democrats' bid to impeach him. "It's disrespectful to boo because he is our president," said Nico Ferranti, 30, adding that he was unsurprised to see the president turn up."He's from New York and he likes this kind of stuff. Back in the day he was on Wrestlemania," said Ferranti, referring to Trump's infamous scripted bodyslam of WWE President Vince McMahon in 2007.Several dozen protesters carrying placards with slogans such as "Trump/Pence Out Now!" and "Headlock Him Up", in reference to a UFC move, demonstrated outside the Manhattan venue.Inside, the president, 73, looked concerned as a lightweight fighter delivered a brutal left kick to his rival's face during the first bout on the main card.The contact, which left the fighter sprawled on the ground for around 30 seconds, drew loud gasps from the capacity crowd as they watched the slow-motion replay of his face being squished.Trump, who spent three hours at the fight night, could be seen clapping in support when the felled fighter finally got to his feet.He also heards fans chant "USA" as an American brawler triumphed over his Bulgarian counterpart. In the crowd, sporadic, alcohol-fueled fights broke out. At least two people were dragged away by security in just one section.Down below, ring girls wearing just shorts and a bra walked around the periphery of the cage carrying boards above their heads displaying the number of the next round. 'The Rock'The president attended with sons Donald Jr and Eric, and several Republican leaders. All three Trumps retweeted a video showing spectators applauding the TV reality star-turned politician."I cheered for him," said Ilya Dibner, who had travelled from Philadelphia for the event."I may not agree with his policies but it's cool he's sitting out there with the people when he could be in a box."Trump has long been a fan of UFC, hosting events at his hotels, and is known to be close to its president Dana White, who has publicly backed POTUS.He was due to stay overnight at Trump Tower on Fifth Avenue before leaving Sunday morning, a departure that coincides with New York's marathon, adding to fears of traffic chaos in the Big Apple.Trump's visit came two days after he announced that he and his family would be changing their main residency from New York to Florida, where tax rates are lower.Trump left shortly before 1:00 am after Jorge Masvidal defeated Nate Diaz for the "BMF" belt in the night's final fight. Wrestler-turned actor Dwayne Johnson, known as "The Rock", presented the belt.