Some of the victims who were treated for injuries suffered in Thursday's deadly bus rollover on I-84 in Orange County are improving, according to the Farmingdale School District.

A Westchester Medical Center spokesperson told News 12 Saturday two of the injured are now in good condition. Two others are in fair condition while one patient remains in serious condition.

Other patients were treated and released, the spokesperson added.

The news comes a day after the National Transportation Safety Board launched an investigation into the crash. Investigators are trying to determine what caused a bus filled with four adults and 40 members of the Farmingdale High School marching band to plummet into a 50-foot ravine on I-84 in Wawayanda.

Two adults were killed in the accident. Authorities identified them as 43-year-old Gina Pellettiere and 77-year-old volunteer chaperone Beatrice Ferrari.

The NTSB said it plans to remain at the scene of the crash for about a week during its investigation. Investigators will interview the victims and driver, as well as examine the bus mechanics.

Investigators are also asking that anyone who witnessed the bus accident, or who has dashcam video to contact New York State police at 845-344-5300.