One worker was killed and another injured Thursday in a construction accident at an Orange County high school, authorities said.

Two workers were reported injured around 10:21 a.m. at a construction site at Villa Park High School, the Orange County Fire Authority wrote in a social media post. The accident occurred when the bleachers in the hall, which were being upgraded, collapsed, according to several news outlets.

After Orange County sheriff’s deputies and fire paramedics responded, one worker was taken to a local trauma center and the second was pronounced dead at the scene, fire officials said.

No students or staff were involved or injured and there is no threat to the school, said authorities, who did not specify the circumstances of the accident. No other details were available.

The Orange Unified School District said in a social media post that counselors were available to staff and students.

The California Division of Occupational Safety and Health said it is investigating the incident, which could take up to six months. The agency can issue citations if health and safety violations are found.