ROCHESTER, Ind.  — A northern Indiana woman accused of striking and killing three children with a pickup truck as they crossed a highway to board a school bus entered a preliminary not guilty plea Thursday.

24 year old Alyssa Shepherd  appeared before a Fulton County judge on three counts of reckless homicide. The Rochester, Indiana, woman also faces one misdemeanor count of passing a school bus when an arm signal device is extended, causing bodily injury.

Shepherd was driving a pickup truck before dawn Oct. 30 when she struck four children who were crossing a two-lane road to board a Tippecanoe Valley School Corp. bus near Rochester.

Six-year-old twin brothers Xzavier and Mason Ingle, and their 9-year-old sister, Alivia Stahl, were killed. An 11-year-old boy who was severely injured in the crash remains hospitalized in Fort Wayne.

Shepherd told authorities she didn’t realize that she was approaching a stopped school bus, despite the activated stop arm and flashing lights.