MADISON, Wis. (AP) — The National Transportation Safety Board has opened an investigation into a chain-reaction crash that killed four people and injured several others in southern Wisconsin last week. The NTSB tweeted that the agency is coordinating the investigation with the Wisconsin State Patrol and does not plan to send NTSB investigators to the scene near Lodi at this time. Eight vehicles were involved in the Friday morning crash that happened as traffic moved around an earlier crash scene. Authorities say a tractor trailer drove into the end of a traffic line and collided with multiple vehicles.
