Houston Independent School District released a statement saying a female student died at the scene Tuesday, while another girl died at a hospital.
Houston police spokesman Victor Senties says a car may have hit the bus after swerving to avoid another vehicle, causing the bus driver to overcorrect and go over the overpass. Senties says the investigation is ongoing.
Names and ages of the victims weren’t immediately released. The district says the bus driver and two other students are seriously hurt.
The bus was bound for Furr High School, which also operates a charter school.
Houston operates the largest public school district in Texas with about 215,000 students.