Both lanes of northbound U.S. 1 have been shut down in Titusville after a traffic incident at Riveredge Drive.
Traffic is being diverted off the thoroughfare to State Road 405 around the scene of the incident.
Police and fire units are working the scene between State Road 50 and State Road 405 and traffic is backing up as it approaches the cloverleaf at SR 405.
According to Brevard County Fire-Rescue, one victim was classified a trauma alert, and five others received less-serious injuries. At least one victim had to be extricated from the wreckage.