US President Donald Trump was booed during the NBA Finals matchup at Madison Square Garden on Monday, as his attendance prompted ultra-tight security at the storied New York venue. Fans jeered the Republican leader, who was watching the game from an executive suite, when he appeared onscreen inside the arena during the singing of the national anthem. Security measures were hiked for the visit, with authorities barring fans without tickets from coming within several blocks of Madison Square Garden. They also banned watch parties directly outside the Manhattan venue – a break from the first two playoff games between the Knicks and the San Antonio Spurs, which drew jubilant crowds. Read moreNBA: Wembanyama within sight of 'childhood dream' after Spurs stun Thunder Officials urged ticket holders to arrive at least two hours before the 8:30pm (0030 GMT Tuesday) tip-off to clear airport-style security screening. Bags were not permitted inside. "The message is simple: celebrate the Knicks, but avoid the MSG area tonight if you do not have tickets for the game," NYPD Commissioner Jessica Tisch told a news conference. Victor Wembanyama scored 32 points to spark the San Antonio Spurs over New York 115-111 in the NBA Finals on Monday, snapping the Knicks' 13-game win streak. Frenchman Wembanyama added eight rebounds, six assists, three blocks and two steals at Madison Square Garden as the Spurs cut the Knicks' lead to 2-1 in the best-of-seven championship series. "We've done what we were supposed to do but the job is absolutely not done," the 22-year-old Wembanyama said. "We're not even halfway. The hardest is yet to come." Ahead of the game, AFP journalists saw a 10-foot (three-metre) fence around parts of Madison Square Garden and a large presence of Secret Service personnel charged with protecting the US president. The agents, some heavily armed, were accompanied by hundreds of NYPD officers as crowds gathered on streets near the venue and at public viewing areas elsewhere in the city. 'Leave us alone'