SHANKSVILLE, Pa. (KDKA/AP) – A raging fire destroyed three buildings at the headquarters complex of the Flight 93 National Memorial in Somerset County on Friday afternoon, but it’s still unknown if any 9/11 artifacts were lost.

In a press release, National Park Service spokesman Mike Litterst said the area must first be declared safe before officials will be allowed on scene to check out the collection storage area.

According to Litterst, an oral history and photo collection were saved, but the condition of the 9/11 flag that flew over the United States Capitol on Sept. 11 it not known.

The flag was presented to the park last month during the 9/11 anniversary observance, and it was being stored on site.

When the staff is allowed back on the site, they will check the condition of the flag.

“It’s very heartbreaking; it really brings you back to that day,” Ken Nacke, whose brother was on Flight 93, told NewsRadio 1020 KDKA’s Bill Rehkopf. “Some of the items from the temporary memorial may have been lost.”

Nacke was instrumental in securing fundraising for the memorial, and working with the victims’ families.

“We gave a lot of personal stuff to the memorial, that we wanted to be shared with everyone, the more and more I think about it, the more heartbreaking it becomes,” Nacke said.

Litterst says “only 10 percent of the Flight 93 National Memorial collection was kept on-site,” and many of the artifacts are stored in fireproof safes.

The Congressional Medal of Honor, presented there last month, was not in the complex when the fire broke out, the press release said.

Nacke says messages, and notes that were left on a temporary fence after the 9/11 crash were being stored in the area where the fire burned.

“You could read messages or notes and letters left by visitors that were actually very touching and heartwarming how the expressed their feelings about what the heroes of Flight 93 did that day.”

“It was amazing thing to see since you know for it being just a piece of fence that was stretched high and long where people could just stop by and leave tributes behind,” said Nacke. “I know for my family alone that was a very comforting spot to go to visit even though you were several hundred yards away from the actual impact site.”

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