A rodeo bull called Party Bus hopped a fence at an Oregon arena and ran through a concession area into a parking lot, injuring at least three people along the way before wranglers caught up with it, officials have said.

The crowd at the 84th Sisters Rodeo in the city of Sisters was singing along with Lee Greenwood's God Bless the USA on Saturday night, local time, when the bull hopped the fence, according to a video shot by a fan.

Other videos posted online, showed Party Bus running through the concession area, knocking over a garbage can and sending people scrambling. The bull lifted one woman off the ground, spun her end over end, and bounced her off its horns before she hit the ground.

The Sisters Rodeo Association issued a statement on Sunday saying three people were injured "as a direct result of the bull, two of whom were transported to a local hospital," KTVZ-TV reported. 

Rodeo livestock professionals secured the bull next to livestock holding pens and placed it in a pen, the association said.

Deschutes County Sheriff's Sergeant Joshua Spano said several ambulances were called, and deputies transported one patient with non-life-threatening injuries to a hospital.

One deputy also sustained minor injuries when responding to the bull's escape, Lieutenant Jayson Janes told KTVZ on Sunday.

Danielle Smithers was among the rodeo fans in the stands as the bull was moving around the ring with two riders on horseback.

"And about 30 seconds into it I stopped and I looked at it and I thought to myself, 'This is just too beautiful not to have a video,'" Ms Smithers said. 

"[I] started recording the bull, just following him, making his loop and as he started coming around his second loop in my video, he goes right over the fence," she said.

The Professional Rodeo Cowboys Association (PRCA) said the incident is a reminder that "while rodeo is a highly-entertaining sport, on very rare occasions it can also pose some risk".

"PRCA sends our thoughts and well wishes to those who were injured or otherwise impacted by this frightening and very rare incident," the association said.

Officials with the Sisters Rodeo couldn't be reached to ask if an investigation is planned.

The rodeo's final performance on Sunday went on as scheduled.

AP