EGG HARBOR TOWNSHIP — Explosions and a fire led to the evacuation of hundreds of employees at the William J. Hughes Technical Center on Friday as multiple fire companies rushed to combat the blaze.

Federal Aviation Administration officials have since assessed the damage and are now coming up with a plan to clean up and make repairs, FAA spokesperson Kathleen Bergen said Saturday morning. She anticipated releasing further details at around noon.

None of the employees was injured, although three firefighters were sent to an area hospital with heat-related injuries, said Kevin Rehmann, a spokesman for the South Jersey Transportation Authority, whose fire department was in command of the scene.

Friday’s fire remains under investigation Saturday, Atlantic County Fire Marshal Harold “Whitey” Swartz said, with investigators seeking to explain what caused the fire and smoke that damaged the building.

Swartz said Egg Harbor Township and State Police fire investigators were both reviewing the fire damage.

The Federal Aviation Administration evaluated the damage, a spokesperson said, with a contractors preparing Saturday to remove debris and water from the second and third floors of Building 300, the main administrative building, that was damaged in the blaze.

The Tech Center will be open for business on Monday, FAA spokesperson Kathleen Bergen said. Employees and contractors should report to work as normal, unless contacted by supervisors.

The cafeteria will be closed. Additionally, Bergen said about 230 employees will have to use temporary workstations in the atrium and auditorium because the fire rendered their work areas inaccessible.

Three explosions — two large ones followed by a smaller blast — rocked the complex, according to witnesses who reported hearing alarms shortly afterward. They said the explosions seemed to be centered in Building 300. The Tech Center is the national scientific test base for the FAA, and the fire contributed to national air traffic control problems.

“The smoke wasn’t dark at first — real heavy but light-colored,” said Ken Golley, an air traffic systems technician at the center. “After that first good blast, we saw dark smoke and flames coming out of the building.”

Several witnesses said the explosions might have come from propane tanks on the site, but the cause of the fire was unclear Friday. Atlantic County Fire Marshal Whitey Swartz said the fire began on the roof and spread inside the building.

FAA spokeswoman Holly Baker said employees were evacuated from Buildings 300 and 316, where 1,600 people work.

Building 300, the main administration building, sustained extensive water and smoke damage. Contractors were working on the roof at the time of the fire, Baker said.

The bulk of the roof blaze, which broke out about 12:30 p.m., was extinguished about 2:30 p.m. However, firefighters continued to check for hot spots and burning embers that could spread inside the building, he said.

“It burned in the building,” Swartz said of the fire.

Weather became an obstacle for firefighters as a bulletin was issued about 2 p.m. warning of lightning strikes within six miles of the center, Swartz said. Firefighters were forced to withdraw from the roof and ladders when there was a chance of lightning, he said.

AtlantiCare Regional Medical Center spokesman Frank Tedesco said the Mainland Campus in Galloway Township treated and released three firefighters who had responded to the blaze at the Tech Center.

A spokesman for Shore Medical Center in Somers Point said the hospital had not received any patients because of the fire as of 5 p.m.

As firefighters fought the blaze, police blocked access to the Tech Center and the Atlantic City International Airport at Terminal Road as light-colored smoke billowed into the sky above the campus. Airport access was reopened about 2 p.m.

Kris Preisner, a computer engineer at the FAA, was waiting at the roadblock, talking to co-workers. He said his team made it out.

“We train for this every few months,” he said. “I think we were prepared, and the evacuation went smoothly.”

Preisner lives nearby in Egg Harbor Township and returned to the scene after lunch to discover the road blocked off.

“It was crazy to come back and see all of this smoke,” he said.

Employees who had evacuated the Tech Center gathered at the nearby Wawa and at Christi’s Bar and Restaurant on the Airport Circle. They talked about their experiences that day and discussed whether they would be able to return to work next week.

Dawn Evans, a computer specialist who lives in the Bargaintown section of the township, said the center held regular fire drills. It wasn’t immediately apparent whether the alarms were for a drill or not, she said.

“We knew it wasn’t a fake fire drill when we saw smoke coming off the building,” she said. “But it was very orderly despite the chaos.”

Tricia Dillon, an Egg Harbor Township resident who works in Building 316, said construction had been ongoing for a while in Building 300. During the evacuation, she noticed cars covered in ash in the parking lot.

“At first we thought it might have been a terrorist attack, and we all ran,” she said.

Golley, a resident of the English Creek section of the township, said evacuees lingered near the campus until after the explosions made it apparent they would not be returning to work.

“At the time of the second blast, we all started to go home,” he said. “With the fire like that, you’re not going back in the building.”

U.S. Rep. Frank LoBiondo, R-2nd, said he was watching developments closely. The Tech Center represents a large part of the local economy, he said, with the impact of the technology being developed there being felt across the country.

“(It’s) the premier facility in the nation for safety and security research and development,” he said, adding, “I’m very anxious about the extent of the damage and waiting for a detailed report.”

Rehmann said Atlantic City International remained open to flights for the duration of the fire.

As of 4 p.m., there were only minor delays.

Rehmann said the incident will be investigated by the Atlantic County Prosecutor’s Office. A spokeswoman for the office said she had received no information on the fire.

Staff Writers Lynda Cohen, Derek Harper, Joel Landau and Rob Spahr contributed to this report.

Contact Wallace McKelvey:

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