The intersection has traffic lights and its reasonably visible. It sounds like catastrophic mechanical failure with wet roads {rainy day in East Tennessee} as a factor. Not sure if the river fog would factor in either. But that intersection is a few hundred yards from the river bridge.
Knox County like many other counties in the area made the huge mistake of middle and high school consolidations. Kids that once went to Holston High now go to Gibbs High and former Gibbs Middle school go to Holston. Bus routes are much longer than a few years ago and more dangerous roads are being driven as a result.
Prayers for the families. I wish the bus companies would go back to using conventional long nose buses. It might have made a big difference in a wreck like this one.
Looks like one of the buses ran a red light and struck the other.
That is my understanding as well. The weather here was (and still is) rainy, and the slick roads have been a factor in several accidents today. No way to know yet if that contributed to this accident, but it's certainly possible.