It happened around 9:45 p.m. near the intersection of 16th Street and Larimer Avenue.
RTD Spokesman Scott Reed says the bus driver honked at the cyclist, but instead the noise startled him. Reed says a witness told RTD the cyclist then slammed on his brakes and flew over his handlebars and the bus driver ran over his right leg.
The cyclist was transported to a local hospital in serious condition, according to Reed. He says Denver Police have told him the cyclist was 72 years old.
The cyclist's name has not been released.
Reed says about 25 years ago, an exception was made to allow for bicycles on the 16th Street Mall on Sundays. He says he thinks it may be time to revisit the exception because there is more bicycle traffic now.
The driver is currently on suspension pending the outcome of the investigation, which is standard practice for RTD.
Police have not said if anyone will face charges in the incident.
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