Simplify the following text for a Grade 6 native English-speaking person.
Original: 6 of the total of 8 cars of the train on the Joetsu Shinkansen derailed near Nagaoka Station in Nagaoka , Niigata .
Simplified: Eight of ten cars of the Toki No. 325 train on the JÅ etsu Shinkansen derailed near Nagaoka Station in Nagaoka , Niigata .