Updated

Three young siblings were struck by a vehicle and killed at an Indiana school bus stop on Tuesday morning, and the suspected driver was arrested, state police said.

The suspect, Alyssa L. Shepherd, 24, was taken into custody around 4 p.m. at her workplace in Rochester, Indiana State Police said in a news release posted on Twitter. A warrant for her arrest included "three felony charges of reckless homicide," as well as "a misdemeanor count for passing a school bus, with the stop arm extended, causing injury."

Law enforcement arrived at the scene of "a single-vehicle crash" about 7:15 a.m., state police said. A preliminary investigation found that the school bus driver, Robert Reid, 46, was northbound on State Road 25, according to police.

"Reid stopped the school bus in front of a mobile home park at 4684 North State Road 25. He activated the buses’ stop arm and exterior lighting, as he was picking up children from the west side of the road," the news release said. "As children crossed the road, to get on the bus, four children were allegedly hit by a southbound 2017 Toyota Tacoma" driven by Shepherd.

Three children -- identified as twin brothers Xzavier and Mason Ingle, 6, and Alivia Stahl, 9, their sister -- were killed in the crash, state police said. An 11-year-old boy, Maverik Lowe, suffered "critical injuries" and was airlifted to a Fort Wayne hospital, police said.

"At last check, he was in surgery with multiple broken bones and internal injuries," the news release said. "The six year-old boys, and their sister, attended Mentone Elementary School. Lowe attended Tippecanoe Valley Middle School."

An investigation is ongoing. Shepherd was being held at Fulton County Jail, with a surety bond of $15,000, state police said.

The state police initially tweeted about the crash shortly before 9 a.m. Tuesday, saying the agency was "investigating a fatal crash in Fulton County."

“Preliminary info is three children were struck & killed at a school bus stop near 4600 N State Road 25,” Indiana State Police said in a tweet.

It wasn’t immediately clear if the driver of the vehicle had stayed at the scene.