HAGERSTOWN, Md. (DC News Now) — Construction crews were cleared to be back on the job Friday after buried explosives were found at a work site.

Two hotels and a Sam’s Club store off of Halfway Boulevard near Interstate 81 were evacuated while the fire marshal restored the area to safety.

“We were on the phone with the fire emergency department telling us to evacuate within 30 minutes,” Racha Iskandara with the Homes2Suites Hotel said.

Al Sadler, the general manager of the hotel said they had to go door to door.

“Even to doors that had a ‘Do Not Disturb’ sign on the knob,” he said. “We cleaned the house, even at our other hotel.”

State Fire Marshal Oliver Alkire said the explosives were undetonated from previous work crews and they could date back to the early 1980’s. Though the situation still had to be approached with caution, he said.

“We ask folks to follow the 3 R’s,” Alkire said. “Recognize the device. If you are not familiar with it, retreat. Finally, report it. Call 911.”

Calls about possible explosives are not all that uncommon in the area, according to Alkire.

“A vast majority of our calls are from discovery of old Civil War rounds,” he said. “That’s not all that uncommon in an area with as much history as there is.”