The A30 is closed this morning after two people died in a crash last night.
Police and emergency services are investigating the scene at Crowlas after a crash between a car and a lorry at about 9.50pm.
The road is expected to be closed until mid-morning and diversions have been put in place.
Des Tidbury, Cornwall Fire and Rescue Service chief, confirmed this morning that two people had died.
The fire service sent two crews from Penzance, one Pumping Appliance from St Ives and the Rescue Tender from Camborne.
Neil Sterio from the Highways Agency said the road could be closed until midday or beyond.
He said: "A diversion is in place with southbound traffic joining the B3302 from the A30 north of Erth and travelling south east - joining the A394 for Penzance west of Helston. Northbound drivers will need to follow the same diversion in reverse."
The Highways Agency is advising drivers to avoid the area if they wish to avoid congestion as the diversion route and local roads are likely to be very busy.