The accident involved three 100-pound propane tanks where a new museum is being built.
The fire, which broke out shortly before noon, reached two alarms. The evacuations led to long lines of tourists trying to board ferries.
Long lines of people leaving #liberty #island after a construction accident involving a propane tank. No boats heading to the island right now More soon @abc7ny #abc7ny #fdny #nypd pic.twitter.com/9AFzsdKewN— Kemberly Richardson (@kemrichardson7) August 27, 2018
Ferries carrying tourists to the island were halted until mid-afternoon.
"I saw it burn, just ran," one witness said. "It popped, and we just started running. And they started blocking the section."
FDNY Manhattan Borough Commander Roger Sakowich said the fire created a very dangerous situation.
"With that much propane, a BLEVE (boiling liquid expanding vapor explosion), which would have been one of the tanks exploding, could have been catastrophic," he said. "Anybody near it, shrap-metal would have been flying for quite some distance, plus a tremendous ball of fire when a propane tank does explode like that. So we took the precaution to evacuate 3,400 civilians from the island."
One construction worker was treated on scene for minor burns. No other injuries were reported.
The FDNY said the flames were extinguished around 12:45 p.m., but crews continued to hose the propane tanks to cool them until the situation was declared under control around 1:30 p.m.
Crews used sea water from five boats in the river to battle the fire.
WATCH the FDNY briefing on the fire
Investigators were still working to determine the exact cause of the fire.
Construction crews have been working on a new Statue of Liberty Museum, which is slated to be completed next year, and a new screening facility, which is set to be completed later this year.
WATCH raw video from NewsCopter7 of the fire and evacuations
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