A 74-year-old woman was killed in a bizarre accident in Western New York where a rock shot through a windshield and struck the woman in the head as she rode as a passenger inside the vehicle. 

Deputies with the Ontario County Sheriff's Office are still trying to determine whether the rock - measured at 5 inches wide, by 2 inches high, by 3 inches long - sprung from the roadway by force of a tractor trailer tire, or if it was ejected from the tractor trailer itself.

It happened midday Saturday on Routes 5 and 20 in the town of Seneca. Barbara Amidon of Waterloo was traveling with Gregory Sterman, of Geneva, when the incident occurred, MPNnow.com reported:

During a press conference Sunday, Lt. David Cirencione with the Ontario County Sheriff's Office said in his 16 years with the Sheriff's Office he has never known anything like this to happen. Rocks, deer and other objects strike windshields, he said, but never has a rock penetrated a windshield and killed someone.

Reports indicate Sterman acted immediately, taking the Amodion woman to nearby Geneva General Hospital; She was soon flown to Strong Hospital, where she succumbed to her injuries Saturday night, the report said.

It remain unclear whether the driver of the 18-wheeler in front of Sterman and Amodion is aware of what occurred. The Ontario Country Sheriff's Office is asking motorists who were traveling Routes 5 and 20 between Flint and Geneva on Saturday between 11:55 a.m and 12:10 p.m. to call them at 800 394-4560.