Willie Hernon, 42, is charged with murder and armed criminal action and is being held on $1 million bond. Taiya Herndon, 45, is charged with hindering prosecution and has a $500,000 bond. The couple were arrested in Caseyville, Illinois, and are awaiting extradition to St. Louis County.

The victim, Alyssa Wilson, was driving to a Halloween event at a zoo when she was shot and killed. Her father, Robert Hickman, said she was looking forward to turning 18 and to a family trip to Disney World, where she hoped to see Princess Tiana.

Investigators say surveillance footage showed a vehicle pull onto the right shoulder of Interstate 170 and turn on its hazard lights. About a minute and a half later, a person got out of the passenger side. Wilson’s car approached moments afterward, and the recording captured the sound of a gunshot. Her vehicle then crashed. The suspect vehicle pulled back onto the highway and left the scene.

Authorities said the evidence did not point to road rage and indicated the suspects did not know Wilson. The day after the shooting, investigators found a cartridge case consistent with a high-powered rifle in grass near where the vehicle had stopped. License-plate recognition helped investigators locate the couple at an Illinois hotel, despite a reported plate swap; a Razorbacks logo visible on the vehicle in surveillance footage helped identify it.

Authorities have not released information about a possible motive. The investigation is ongoing. The charges are allegations, and the defendants are presumed innocent unless proven guilty in court.