All of the patients treated at the University of Maryland Medical System's Harford County hospitals have been discharged following Monday's bus crash on Interstate 95, according to a statement from the system.

Harford Memorial Hospital in Havre de Grace treated 17 patients. Upper Chesapeake Medical Center in Bel Air treated nine patients. Two of those patients were discharged into the care of the Children's Hospital of Philadelphia. All but four students and one teacher remain hospitalized.

One child and one adult were critically injured in the wreck. The adult was airlifted to Shock Trauma in Baltimore, while the child was flown by Delaware State Police to the Alfred I. duPont Hospital for Children in Wilmington. 

Maryland State Police released 911 calls from the crash scene:

The School District of Philadelphia says one child was released from the hospital Tuesday morning.

Philadelphia School District Spokesman Lee Whack says the hospitalized teacher is Brittany Jacobs, a special education teacher at Charles W. Henry School. University of Maryland Medical System spokesman Michael Schwartzberg says Jacobs is in critical condition.

The bus carrying 26 children from the school, three chaperones and the driver overturned at least once near Havre de Grace. Police say a car that tried to pass the bus clipped it.

The names and conditions of the four children haven't been released.

Maryland State Police on Tuesday identified the passenger car's driver as Menachem Backman, 20, of College Park. Charges against him are pending the outcome of an investigation and consultation with Harford County prosecutors. Backman refused treatment at the scene.

The driver of the Werner charter bus was identified as Clarence Beamer, 59, of Philadelphia. In all, 30 people were taken from the scene to area hospitals, state police say.