Police in Santa Fe, Texas, said they found multiple explosive devices in and around the school campus where at least eight people were killed in a shooting on Friday.
Law enforcement authorities are reported to be actively searching for more devices, according to CBS News.
A male student was taken into custody after the shooting, and another person of interest, also a student, was reportedly questioned by authorities.
Police have locked down and evacuated Santa Fe High School, located about 30 miles from Houston, county police said.
The U.S. Bureau of Alcohol, Tobacco, Firearms and Explosives is on the scene, along with police from Galveston County.
No victims have been immediately identified, though most are believed to have been students, and one of those who was injured is reported to be a school resource officer.