Police arrested a man accused of bringing an AR-15 to Rio Grande City High School on Tuesday, according to a news release from the district.

The male, who has not been identified by authorities, said he was on school grounds to pick up his sister when a security guard spotted the weapon in the front seat of his vehicle, according to the Rio Grande City Grulla Independent School District.

“The security guard immediately notified campus police department, and they apprehended the individual,” the district stated in a social media post. “This individual has been arrested and is now awaiting official processing.”

The male subject did not come into close or direct contact with students and staff, and students were not in danger, the district added.