Hazardous materials specialists are still at the scene of chemical leak at a transport company in Christchurch.
The specialists, in protective clothing, have been smothering the chemical which escaped from a drum in a freight yard in Wigram on Sunday morning.
Firefighters are also still at the scene, as a precaution.
The fire service says it still does not know what the chemical is or what caused the leak.
Four truck company workers were taken to hospital as a precaution following exposure to the substance.