New pictures have shown the wider extent of carnage caused following a collision in Hanger Lane .
The crash, which resulted in a car lying on its side in a subway entrance, sent a barrier pole flying which smashed an office window.
Adam Field arrived at his office, The Best Connection in Hanger Lane, Park Royal, shortly before 7am on Wednesday (December 28) to discover the damage.
He said the smashed glass had spread up to 30ft around the office onto tables and chairs, adding he believed someone could have been hurt if they had been inside.
Mr Field, who has been branch manager for one year, said: "I arrived at 6.50am and found a barrier pole had gone through my front door.
"It was one of the metal railings. It caused damage to the gate, the shutters going across the front and the window.
"Outside I was surprised to find glass shattered at my office.
"The glass could have hurt someone, it went flying across the office. There was hole.
"It had gone everything from chairs to desks, it flew around 20 to 30 feet across the office.
"We have got boarding over it at the moment."
Metropolitan Police said it was called to the scene to reports of a collision, but said the driver had left before officers arrived.
The car reportedly went onto the roundabout, through a barrier and down into the subway entrance outside Hanger Lane station.
A London Underground supervisor yesterday described the "unbelievable" moment he saw a man climb out of a car unhurt following the crash.
Transport for London (TfL) supervisor, Michael Macefield, had been working through the night at Hanger Lane station when he heard a "loud bang" at around 5am.
The Hammersmith resident left his office and was astonished to see the car had landed outside the subway entrance.
But to his amazement, Mr Macefield said the driver climbed out of the car unhurt before climbing back in to get his possessions before leaving the scene.
No arrests have yet been made.
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