H.E. Bonner Elementary School north of Moncks Corner was placed on lockdown Wednesday morning when officials there spotted what they thought were three men with guns outside, authorities said.
Deputies from the Berkeley County Sheriff's Office investigated the alleged sighting, though, and came across three men who were surveying land, agency spokesman Dan Moon said.
None of them had firearms, he said.
"They were just land surveyors surveying land," Moon said. "But it's better safe than sorry."
The administrative lockdown, which called for all exterior doors to be locked, had gone into effect after 10:30 a.m., Berkeley County School District spokeswoman Susan Haire said.
It came as a suggestion from law enforcement officials, she added, while deputies investigated the "community disturbance."
The school is at 171 Macedonia Foxes Circle near the intersection of U.S. Highway 17A and Bethera Road.
Deputies determined less than an hour later that the report had been unfounded.
Reach Andrew Knapp at 937-5414 or twitter.com/offlede.