A gas tanker has crashed over a bridge and plunged 50ft on to a railway near a market town in County Durham.
An exclusion zone has been set up and the driver was airlifted to hospital after the crash at the Weardale Railway just outside Wolsingham.
Potentially flammable gas is reported to be leaking from the tanker and a 100m cordon is in place. A few homes and a caravan park were evacuated.
The driver was thrown from the tanker - the extent of his injuries is unclear.
Police and fire crews are at the scene and the A689 has been closed.
In May, a van containing gas cylinders exploded in the town's market place, killing the driver and causing widespread damage to both residential and commercial properties.
