Authorities in Kansas have found the semi-trailer that was involved in a two-vehicle wreck last week south of Olathe.

The driver of the semi said he was unaware his vehicle had been rear-ended. The accident occurred early Wednesday when a vehicle rear-ended the semi on northbound Interstate 35, just north of 175th Street, the Kansas Highway Patrol reported.

A pregnant Gardner woman injured in the accident later delivered a healthy baby girl. Nikki McClure, 33, remains in critical but stable condition at Overland Park Regional Medical Center. The baby is in stable condition but remains in intensive care, said Christine Hamele, hospital spokeswoman.

Authorities said the accident occurred when McClure’s Hyundai sedan hit the trailer. The semi kept going with the hood of the car impaled on the back of the trailer. The fully loaded semi weighed approximately 80,000 pounds, and the semi’s co-drivers were unaware the accident had even occurred, Lt. Tom Catania said in a release.

It is not uncommon for occupants of vehicles of that size and weight to be unaware of a crash if they are struck by a passenger car, he said.

Witnessed notified authorities after media accounts of the accident. Officials with the trucking company were cooperating with authorities, Catania said.