The A69 is closed between Brampton at the A6071 and Naworth Crossroads due to a multi-vehicle collision.
Emergency services, including police and fire crews were called to the incident, which happened at about 9.15am.
A statement from Carlisle East Fire Station said: “The crew are now on their way back from the road traffic collision on the A69 near to Brampton. The collision involved three cars and a van, and crews extricated three casualties from one car and a casualty from the van.”
They added injuries were not believed to be serious.
Police said the road was due to be closed for several hours and urged drivers to avoid the area.