Police in Philadelphia say it's a "miracle" all four passengers - including an infant - survived when the helicoper they were travelling in crash landed in a built up area.
The Eurocopter EC135 aircraft somehow managed to avoid power cables and buildings before it hit the street and slid into bushes outside a Methodist Church, officers added.
Rescue crews arrived at the crash at about 1pm on Tuesday and helped get the pilot, two crew members and the infant out of the aircraft before taking the child to hospital.
It had taken off from outside Philadelphia and is believed to have encountered mechanical problems during the flight, a spokesperson from the Pennsylvania Emergency Management Agency said.
'Miracle' passengers survived
Dramatic pictures showed the helicopter on its side outside the church.
"It's a miracle, it's an absolute miracle, here what you see behind me," Superintendent Timothy Bernhardt said.
Joshua James said he was driving nearby with his wife and young son when he saw the tail of the helicopter swaying back and forth as it slid to a stop - forcing him to suddenly put his car in reverse.
"It makes no sense to me that it didn't hit any of the wires or anything - that it didn't hit us," Mr James said.
Another witness, Jerrell Saunders, 28, said he was walking from a maintenance job at an apartment building when he saw the helicopter "just floating, like real low, like extremely low, like it could land on the building that I work at".
He said the helicopter was going in the same direction as he was driving, and he saw it hit the ground in the middle of the road and slide across the groundbefore coming to a stop.
"I guess the pilot tried to land in a safe area, because it took a bounce on the ground and fell and, like, slid," Mr Saunders added.
Federal investigation launched
He said the helicopter turned on its side and as smoke came out as he saw people jumping out of it.
A fire official said the aircraft had about an hour's worth of fuel left at the time of the crash, and crews took steps to keep leaking fuel out from contaminating the water.
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