A driver accused in an accident at a school bus stop killed three siblings

Three children from the same family were killed and a fourth child was seriously injured Tuesday morning when they were hit by a van while they were preparing to board a school bus, police said.

The two identical twin brothers, Xzavier and Mason Ingle, aged 6, and their 9-year-old sister Alivia Stahl, were killed in the incident on a rural road in Indiana, said the Sgt. Tony Slocum, Information Officer of the Indiana State Police Service.

Maverik Lowe, an 11-year-old boy, had several fractures to the fracture, Slocum said.

The van driver, 24-year-old Alyssa Shepherd, arrested Tuesday afternoon and charged with three counts of irresponsible homicide and one count of negligence charges for her life. a stop sign and injury, officials told ABC News. Shepherd was taken to Fulton County Jail, but was released Tuesday night on bail of $ 15,000, news agency officer Adam Roop, an officer in charge of monitoring the evening prison, told the news agency.

The incident occurred around 7:15 in Rochester, a town near Fort Wayne, Slocum told reporters on the spot. The injured boy was taken to Fort Wayne Parkview Hospital by helicopter and underwent surgery, Slocum said.

The father of the twins came to the scene and identified his children, said Slocum.

"Our hearts are shattered for the families involved in this tragic situation and our prayers go to them, of course," said Slocum. "It was a difficult day to watch the emotions that these family members had to live through and a difficult day for the first responders. It's been a while since I did not see the first responders crying, but I saw tears flowing today because it's this dictated situation. "

The four children were crossing a two-lane road from a mobile home park where they lived to get to their school bus after being hit by a Toyota Tacoma truck, police said. A preliminary investigation showed that the yellow school bus was in the northbound lane of Highway 25, with its hazard warning lights and stop sign lifted when the children were hit by the truck. south direction, said Slocum.

Shepherd of Rochester remained on the scene and cooperated with the police, Slocum said.

The NTSB has set up a "team" of investigators to examine the crash. More than six federal investigators will arrive in Rochester on Wednesday to find out how the children were killed, an NTSB spokesman told ABC News.

The agency will focus on the safety of children when boarding and disembarking a school bus, officials said.

All children attended Mentone Elementary School, located near Menton, Indiana, where Alivia was named Honorary Member in January.

Slocum said the shepherd had been subjected to a blood test to determine the presence of drugs or alcohol. He stated that the investigators had interrogated him, but he had refused to disclose what she had said about the accident.

"We do not know why this accident happened while we are talking here," Slocum said.

Aerial photos of ABC's subsidiary, WLS-TV in Chicago, showed a badly damaged pickup truck at the front of the vehicle.

The Tippecanoe Valley School Corporation issued a statement on Facebook after the incident.

"Our school society was tragically affected this morning, we learned that three students died and that one student was seriously injured and flown to a Fort Wayne hospital while being hit by a vehicle. while he was getting on his bus, we have deployed all the school counselors the emotional needs of our staff, students and parents, "writes the school on Facebook. "We are waiting for more details confirmed, but wish to ask the community to come together to pray for families, our students and our staff."

Jeffrey Cook and Darren Reynolds of ABC News contributed to this report.