An in-store appearance by hot teen singer Reece Mastin at the Warehouse Sylvia Park in Auckland has been cancelled due to severe overcrowding. The in-store was scheduled from 6pm tonight but a correspondent for the Herald reported the event was called off due to heavy crowds. Safety was an issue. There were reports of teenagers fainting and some being trampled. Ambulances were on the scene. Mastin, 16, is the winner of X-Factor Australia and is performing at Wellington\'s TSB Arena on April 12 and Auckland\'s Vector Arena on April 14. \"Had to get outta that bloody crowd for @reecemastin concert at Sylvia park,\" tweeted Gemma Mecchia. \"We came all the way from Hamilton for this and got pushed out of the crowd.\" \"Just waited 6 hours for @reecemastin at sylvia park for it to get cancelled,\" wrote Kendall Martin on Twitter.