NEW YORK (AP) - Paul McCartney is on a roll this week. A day after performing at a New York City high school, the ex-Beatle surprised fans Thursday with an impromptu concert in Times Square. McCartney announced the concert on Twitter and then arrived by taxi at the "Crossroads of the World" an hour later. Despite the short notice, thousands of fans flocked to the busy midtown-Manhattan intersection for the lunchtime concert. The 71-year-old rocker sang four songs from his latest album "New" from a trailer parked on West 46th Street and Broadway. He joked: "Let's do this the same time tomorrow." On Wednesday, McCartney performed and took questions from students at the Frank Sinatra High School in Queens. He was celebrating his second wedding anniversary with Nancy Shevell.