A student was in custody in connection with the discovery of a suspicious backpack at Seven Lakes High School in Katy on Monday.
The district send out an email notification shortly after 1 p.m. to say a student suspect is in custody. No other details about the suspect or the arrest were provided.
Students were going to be sent home at 1:30 p.m., the district's website said.
The district confirmed to KPRC-TV and Click2Houston.com that all students and staff at the school were evacuated for a safety issue around 10 a.m. Monday.
According to the district's website, Katy ISD police learned of a "perceived threat on campus" around 10 a.m. and authorities were called to investigate.
According to an update posted on the district's website, authorities have learned that "a potential explosive device has been identified" inside the school.
According to the Harris County Sheriff's Office, a suspicious backpack was found on the east side of the building near the ninth grade center.
Officials said the Harris County Sheriff's Office bomb squad is at the scene and the FBI has been called to the school to help with the investigation.
More than 3,000 students attend the school.
KPRC-TV and Click2Houston.com are a sister TV station and a sister web site of KSAT.com.