The crash occurred at about 8 p.m. on Tuesday, Oct. 6, along East Park Boulevard near N Avenue, a stretch posted at 30 mph. According to police, two vehicles were traveling side by side at a high rate of speed when one struck a bicyclist who was attempting to cross the road. Neither driver stopped.

"One of the two vehicles struck the pedestrian on the bicycle, and then they continued traveling eastbound, did not stop to render aid or anything else like that. They just left him injured and fled the scene," Plano police spokesman Jerry Minton said.

The bicyclist suffered serious injuries but survived. Minton said the impact was severe and that tourniquets were applied at the scene to stop the bleeding.

"He got hit pretty hard," Minton said.

Police said neither vehicle had its headlights on at the time of the crash, which happened roughly an hour after sunset. A witness told investigators the vehicles appeared to be a black Honda Civic and a white SUV.

More than a month after the collision, detectives are still searching for the drivers involved. Investigators are asking anyone who may have captured the vehicles on home surveillance cameras or dashcam video to come forward, and they are urging the drivers themselves to contact police.

"Let us know who you are so that we can finish out this investigation and get some sort of justice for the person that was struck," Minton said.

The case highlights longstanding concerns about road safety for cyclists and pedestrians in fast-growing Collin County suburbs, where wide arterial roads like East Park Boulevard carry traffic at higher speeds and where people on foot or bike often share the roadway with vehicles. Street racing and vehicles driving without lights after dark pose particular dangers to vulnerable road users.

Anyone with information about the crash or the vehicles involved is asked to contact Plano police.