The building has been deemed too unsafe for people to enter, and structural engineers have been called in.
An employee is still missing after a roof caved in at a warehouse in Prince George's County, Md., around 10 p.m. Thursday.
Rescue workers from the Prince George's County Fire/EMS Department are still trying to reach the victim, believed to be trapped under a 40- to 50-foot-tall pile of debris at a document storage facility.
No one has heard any cries for help.
Efforts were hampered after the building was determined to be unsafe Friday morning, but structural engineers have since developed a plan to resume the search.
Contractors will begin using two cranes to remove large pieces of debris starting at around 3 p.m. Friday. They'll then move into the area where the employee was last seen, and will bring the K-9 unit back. However, it could take five or more hours to get to that point.
In the meantime, rescue workers are trying to fight the day's record-setting temperatures by staying hydrated and resting in a nearby air-conditioned Pepsi Bottling Group building when they're not working.
An employee at the warehouse told NBC4's Melissa Mollet that the cave-in was apparently triggered when another employee, driving a forklift, clipped a long, tall storage shelf. That shelf knocked down others, causing a domino effect as they crashed into at least one support beam.
After three fruitless overnight searches by firefighters, they brought in a K-9 unit. But by 6 a.m. Friday, crews were unable to re-enter the building. Some of the walls were buckling, with audible cracking.
Employees and family members of the missing man, including his wife, were continuing to wait on the scene Friday morning.
Sixteen employees were able to escape from the cave-in.
The missing man's car is still in the parking lot, and calls to his cell phone are going straight to voicemail.
Authorities are still considering this a rescue mission.
Initially there was concern of a possible natural gas explosion, but that has been ruled out and there wasn't a fire.