From the look of a photo of where the van the windie was driving ended up, it would appear to me that the driver of the Citroen pulled out of a side road into the path of his van. It was in the 60mph speed zone, although the windie should only have been travelling at 50mph. His van veered off the road to his left, which indicates to me that he got hit on the right side of his van.
Again, this is very sad, but I hope they release a few more details of the accident, so we can learn from what happened.