Explosives have been found at the Texas high school where a gunman killed at least eight people Friday morning, according to officials.

“There have been explosive items found in the high school and outside the high school,” Santa Fe Independent School District Police Chief Walter Braun said at a press conference.

“Because of this, everyone should be on the lookout for suspicious items and anything that looks out of place.”

Police are also sweeping a mobile home near the school in the town of Santa Fe for possible explosives, according to KHOU11 News.

Some students reported seeing the shooter throwing explosives into a classroom, according to the TV news outlet.