We wonder what music he was listening to.

Incident in Colarado sees enraged headphones-wearing runner take exception to mountain biker’s disparaging head-shaking.

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A mountain biker, referred to only as ‘Andrew’ on 9news.com, was riding up a trial on North Table Mountain last Saturday (March 25th) and ended up catching up with a runner. Andrew alerted the runner to his presence by ringing the bell on his bike.

“When I saw [the runner], I started to ring the bell on my bike that I have to give him a heads up that there was someone behind him… As I passed, I shook my head because wearing headphones that cover both ears or two earbuds when out hiking or riding or running on these crowded trails on a weekend just seems – it’s sort of not a good idea.”

The runner took an exception to this admonishment. Andrew explains: “The runner said, ‘shake your head at me like that again and I’ll beat your a** mother ******.”

No physical exchange happened at this point. Both the runner and Andrew went their separate ways. Unfortunately, Andrew then encountered the same runner on a different trail later on in the ride.

The runner recognised Andrew.

“Without me saying anything or doing anything to provoke [him], [he] grabbed me by throat, separated me from my bike and started shoving me down onto a boulder that was off the side of the trail”.

Andrew was punched repeatedly by the runner in the jaw and side of head. Andrew hit the deck and the runner then “stomped” on his back.

The runner then picked up Andrew’s bike and hurled it off the side of the hill. Both wheels were damaged and the sadlde was broken too.

Rangers were duly informed of the incident but were unable to track down the runner. Investigators are considering the incident a potential assault and felony property crime.

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Mary Ann Bonnell from JeffCo Open Space: “The earbuds prevented that individual from knowing that this cyclist, who was doing everything right, ringing the bell, trying to politely announce himself, trying to pass, just couldn’t get this trail runner’s attention.”

Andrew said “It seemed like he was already not in a good mood and really didn’t need much to provoke him to want to hurt someone.”