Update 7/28/2016: Denver Police are now seeking help identifying the riders.
Update 7/28/2016: WATCH what it looked like inside the 2016 "Kill The Streets" rally.
Update: The event is annual, and Denver police reported no incidents during this year's ride.
Earlier: Dozens of people riding motorcycles shut down I-25 at University Boulevard this afternoon.
Denver 7 reporter Mark Boyle tweeted an image taken in stand-still traffic.
Footage from a CDOT camera shows the group moving down the interstate and, apparently, stopping to play around.
Denver police had no additional information this afternoon.
