Boulder triathlete Richie Cunningham was injured Thursday after he crashed his bike trying to avoid a car that Cunningham said appeared to purposely stop in front of him in a fit of road rage.

Cunningham and three other professional triathletes -- Ben Hoffman, Patrick Evoe and Joe Gambles -- set out for a ride along North 83rd Street Thursday at around 9 a.m. As the triathletes entered the 15000 block of 83rd Street near a downhill left-hand turn, Cunningham said a car passed them over a double-yellow line, honked its horn and "buzzed" them.

"It just went flying by as we were starting to go down the hill," said Cunningham, who was at the head of the group. "Then halfway down the hill, all of a sudden he just slammed on the brakes."

Cunningham said he tried to slow down and initially thought he could make it past the car to the inside. When it became clear that wasn't an option, he was forced to brake hard.

"I just had nothing else to do," he said. "It was either run up the back of him or brake harder. Once I braked I just flipped over the front of the handlebars."

The car took off but Hoffman was able to chase the car and get a license plate number. The Boulder County Sheriff's Office said the case is still under investigation and no tickets have been issued yet, but officials said they do have some basic information about the possible driver.

As for Cunningham -- who was released from the hospital Thursday night -- he suffered a separated shoulder and a broken elbow that might require surgery. Cunningham says it is likely the injuries will keep him out of competition until after September's Ironman 70.3 World Championship in Las Vegas, an event in which Cunningham has placed in the top five four times.

"It's crushing," Cunningham said. "I was having one of my best seasons. I'm 39 soon to be 40. I don't have that much longer to keep competing."

Added Hoffman, "This is his livelihood. It's tough. It's one of those things, I know there are issues between cars and bikes but it is our job to ride bikes."

Both Cunningham and Hoffman said they think the driver stopped intentionally in a fit of road rage. Cunningham said there was no apparent reason for him to have stopped, and the driver appeared agitated when he first passed them.

"Yeah I think he had some road rage," Cunningham said. "I don't know if he got angry cause it was a large group or what."

Added Hoffman, "The feeling for sure is that it was deliberate. It's just one of those things that seemed unnecessary."

Cunningham, an Australian, said he moved from Austin, Texas, partly because he wanted to feel safer about cycling.

"Especially inside Boulder and the immediate surrounding area it's pretty awesome," he said. "The drivers in general are a lot more understanding."

Hoffman, who also trains in Boulder, said he has seen tension between cyclists and motorists but said he generally has not had a problem in Boulder.

"To be perfectly honest, there are enough cyclists and courteous drivers that we have it pretty good here," he said. "But occasionally you have a bad apple... It's just tough when something like this happens. It seems completely senseless."

Cunningham said he is grateful he was with experienced riders when the accident happened, and added a firefighter was in the car behind them and stopped to give him some medical aid. And despite his injuries, Cunningham said he is grateful the accident wasn't worse.

"Luckily I've been doing this a long time," he said. "If it had been an older man or someone with not as much bike skills it could have been a pretty bad tragedy."