Eleven spectators were taken to hospital, one of them seriously injured, after a crash on the opening lap of the Isle of Man Senior TT motorcycle race on Friday, organisers said.
ACU Events said in a statement that the injuries ranged "from slight to serious. None are believed to be life threatening at this time".
The BBC reported British rider Jonathan Howarth crashed on the fast Bray Hill descent - a popular viewing point near the start - soon after setting off. He was unhurt but witnesses reported the bike and debris flying into the crowd.
The race was halted immediately, with a re-start scheduled.
The TT races, which draw throngs of bikers to the island, are generally regarded as the most dangerous in motorcycling with 240 rider fatalities since 1907.
The latest was 43-year-old Japanese Yoshinari Matsushita, who was killed in practice last week. He was the 21st to die at the circuit since 2000.
(Reporting by Alan Baldwin, editing by Mark Meadows)