A suspect was apprehended after a shooting incident that injured four people at the Timberview High School in Arlington on Wednesday.

The incident started after a fight between two students broke out. Witnesses said that during the fight, one of the students drew a weapon and started shooting.

Three individuals were taken to the hospital after the incident. Two of them were in critical condition, while the third one was in stable condition.

A pregnant teacher was injured after falling from a school building. The incident occurred at around 9:20 am, police said. The teacher was not seriously injured. The school is in the city of Arlington but in the Mansfield school district.

The shooter fled the scene on a 2018 silver Dodge Charger. The incident led to a hunt for the suspect, which included agents from the Bureau of Alcohol, Tobacco, Firearms, and Explosives and U.S. Marshals

Timothy George Simpkins, the gunman, surrendered to authorities Wednesday evening. The 18-year-old student was then arrested and charged with three counts of aggravated assault with a deadly weapon.

A SWAT team entered Simpkins’ home Wednesday night. Grand Prairie police officials said they managed to recover the 45-caliber gun that was used in the shooting a few miles away from the school grounds. Simpkins is currently being held in jail on a $75,000 bond.

After hearing about the shooting, some parents rushed to the school. Officers told them to stay away. The school district placed the campus on lockdown after a report of a possible second active shooter. All students and staff members were locked inside their classrooms until police arrived.

It was later announced that the school would not reopen on Thursday. Students and staff members were also notified that after-school activities would be canceled until further notice.