A rodeo bull jumped over a barrier and charged into a crowd of spectators in Oregan on Saturday night.
Four people were taken to hospital after the incident at the 84th Sisters Rodeo and several ambulances attended.
Video from the Oregon arena shows the crowd singing along to God Bless The USA during the last ride of the night just before the bull – named Party Bus – hops over the fence.
Sisters Rodeo Association said after Party Bus jumped the barrier, it charged onto the rodeo grounds and ran to holding pens, where livestock professionals contained it.
Social media videos appear to show that the bull lifted one person off the ground, spun them over and bounced them off its horns outside of the arena.
According to Sky’s partner network NBC, organisers said it was the first time anyone could recall such a breach happening since their first event in 1940.
They added that the bull has been checked out by veterinarians and is believed to be unharmed.
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Party Bus competed in the Sisters Rodeo Xtreme Bull Riding event Wednesday and tied for third in that first round, according to PRCA information.
Events at the arena scheduled for Sunday went ahead as planned.