A multi-vehicle crash in north Denver may have led to another multi-vehicle crash in the backup, causing a total of four injuries.Two people were injured when a motorcycle went under a truck just before 11:30 a.m. Wednesday near 58th Avenue and Logan Street, east of Interstate 25, the Colorado State Patrol said.7NEWS photojournalist Jim Weis said the motorcycle was in pieces from the collision.The CSP said Denver police were trying to pull the motorcycle driver over on I-25 and 58th Avenue when the motorcyclist drove off. Denver police told CSP they did not chase the motorcyclist. They said the crash happened as officers were turning around.Two people on the motorcycle, Stephen Zinanti, 26, and Brittany Pacheco, 18, were taken to the hospital with serious injuries. The CSP said neither Zinanti or Pacheco was wearing a helmet.The motorcycle crash caused a major traffic backup on I-25 and that led to a second crash involving four vehicles.Troopers said a pickup truck, a Toyota Corolla, and a work truck hauling a cement mixer were stopped in traffic on northbound I-25 in the right lane. A semi hit the pickup truck, pushing it into the Toyota Corolla, which was thrown into the cement mixer.The drivers of the pickup truck and Corolla were taken to the hospital. The driver of the Corolla, Thomas Lang, 49, remains in serious condition.Initial reports from the CSP were that three people had died in the two crashes, but then officials said a half-hour later that no one died.The crashes caused extensive backups on I-25 northbound and 58th Avenue at Logan Street.