A Tippecanoe Valley School Corp. bus had stopped and lowered its stop arm around 7 a.m. on the road near Rochester just before a northbound pickup truck slammed into the children as they crossed the southbound lane, Indiana State Police Sgt. Tony Slocum said.
Six-year-old twin brothers Xzavier and Mason Ingle and their 9-year-old sister, Alivia Stahl, died at the scene, he said. The rural Rochester residents were students at nearby Mentone Elementary School.
Slocum said the pickup's driver, Alyssa Shepherd, 24, of Rochester, was arrested and charged with three counts of reckless homicide and one misdemeanor count of passing a school bus when arm signal device is extended, causing bodily injury. Shepherd was being held at the Fulton County Jail on a $15,000 surety bond.
The great-aunt of the three siblings who were killed, Pamela Pugh, told the South Bend Tribune that she was stunned and shaken by their deaths.
"I'm just trying to make sense of all of it. There are no words," she said.
Related: Deadly school bus stop crash in Indiana highlights safety issues
Slocum said an 11-year-old boy not related to the deceased siblings suffered multiple broken bones when he was also hit by the pickup. That child, Maverik Lowe, was in critical condition at a Fort Wayne hospital and was undergoing surgery.
The boy was conscious and speaking to emergency workers before he was airlifted to the hospital, Slocum said.
Slocum said the students had the right of way as they crossed the street from the rural mobile home community where they lived.
"It's an unspeakable tragedy," he said. "We all have a responsibility to share the roadway and we're all responsible for making sure our children get to and from school safely."
Detectives were interviewing witnesses and a crash reconstruction team was at the scene near Rochester, about 100 miles north of Indianapolis.
The National Transportation Safety Board announced on Twitter that it was sending a team of investigators to the scene that should arrive Wednesday.
The Tippecanoe Valley School Corp. said in a statement posted on Facebook that counselors had been dispatched to its schools to help students, staff and parents. It urged "the community to come together to pray for the families."
Gov. Eric Holcomb said in a statement that he and his wife, Janet, were mourning the students' deaths. He urged Indiana residents to send their "deepest prayers for the strength needed to endure such a time."
"Words cannot express the depth of sorrow Janet and I feel, which only pales in comparison to what family, friends, teachers, classmates and community are feeling right now," Holcomb said.
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