The individual who police allege is responsible for Tuesday’s shooting at Thomas Jefferson High School in Dallas has been arrested, according to the Dallas ISD.

Wednesday night Fox 4 reported, “In a letter to parents Dallas ISD superintendent Dr. Stephanie Elizalde said that the 'individual responsible for the shooting had been arrested.' However, she did not offer any additional information.”

One student was shot in the arm in the school’s parking lot a few minutes after class had let out for the day. According to Elizalde, video of the incident shows a vehicle with two people in it driving up to the scene and one of the people inside the car shooting at the victim standing in the parking lot. The school’s athletic trainer was nearby and provided aid as another school staffer called 911.

According to the report, Elizalde confirms that one of the two people believed to be in the vehicle involved in the shooting is a Thomas Jefferson student, and says the ISD believes the shooting was an isolated incident and that the shooter did not go inside the school. No motive for the shooting has been given by investigators.

The school was closed on Wednesday. That was the same that students returned to class at Lamar High School in Arlington, following the murder of 16-year-old Jashawn Poirier on Monday morning before classes began. The juvenile suspect in the Arlington shooting was arrested soon after the incident and is being held at Tarrant County Juvenile Detention Center.

CBS 11 reported on Thursday that students had returned to Thomas Jefferson High School for classes. Mental health professionals are available to students throughout the day, as there will be an increased police presence until further notice.