A cyclist has been rushed to hospital after a serious crash involving a van on the A30 at Camborne.
Emergency services, including the Air Ambulance, were called to the A30 westbound in Camborne at the Roseworthy junction.
Police report a Daihatsu panel van and a pedal cyclist were involved in the crash at 9.30am today.
A police spokeswoman said: "Both lanes of the A30 were shut at Camborne, Hayle westbound from Portreath and westbound at Tolvaddon to allow the air ambulance to land at the scene safely."
The male cyclist has been taken to Treliske Hospital with severe head and chest injuries.
A HGV lorry is also at the scene and has blocked the road to provide assistance to the emergency teams, say police.
The A30 eastbound between Hayle and Tolvaddon has been reopened.
Drivers are advised to avoid the area for the time being as the road is likely to remain closed for some time.