M74 closed and motorists diverted after road traffic collision Two people have been airlifted to hospital with life-threatening injuries and third taken by ambulance after a car crashed into a bridge support. The incident happened on the M74 northbound at Johnstonebridge, near Lockerbie in Dumfries and Galloway, at around 1.15pm on Saturday. One person has been taken by helicopter to the Edinburgh Royal Infirmary, and two have been taken to Dumfries and Galloway Hospital by air and road, a Scottish Ambulance Service spokeswoman said. A Police Scotland spokeswoman said: "The accident is now being classed as a potential fatal. Two casualties have been airlifted with a further casualty being taken by road. The northbound carriageway is closed and will remain so for some considerable time to allow investigations to be carried out. The southbound carriageway has only one lane open at this time. There is one vehicle involved that has collided with a bridge support on the Northbound Carriageway of the M74, just north of Junction 16 Johnstonebridge.