A busy commuter train had a near-miss after hitting a fallen tree on the line in Hethersett.
The 5.10pm Cambridge to Norwich train, which was travelling at around 75mph, hit the tree between Norwich and Wymondham at around 6.30pm on Thursday evening.
Windows were smashed in the incident, causing the 6.14pm Cambridge to Norwich and the 8.19pm Norwich to Cambridge services to be cancelled.
Chris Spalton, a computer software designer from Norwich who works in Cambridge and was on the train, said: "It's normally a three-carriage train but this was only two carriages so it was quite full.
"Everyone was just minding their own business when all of a sudden there was a huge bang and some debris flew past the window and people were going 'what was that'?
"Everyone on board was fine and remained calm, there was no panic or hysteria.
"The train conductor handled it pretty well. He just taped up the window and after about an hour's delay we limped into Norwich."
The crew on board assessed the state of the line and the train before returning to Norwich.
There is still a blockage on the line meaning that trains between Norwich and Cambridge may be delayed or cancelled.
Greater Anglia and East Midland Trains are expected to be affected by the incident until 9pm.
A spokesperson from Greater Anglia said: "The 17.10 from Cambridge to Norwich hit a tree at Hethersett. Nobody was hurt but the train was damaged.
"The driver was shocked but after a short while was able to drive the train to Norwich.
"We apologise to any customers that were delayed by this incident, we remind them they can claim delay repay."
A spokesperson from Network Rail said: "The incident occurred at 6.30pm this evening and the line between is currently blocked between Ely and Norwich.
"The train has now left the site of the incident. There is minor damage to the train, but no injuries to those on board.
"Engineers are currently on-site working to remove the tree from the line and reopen the railway for passengers."
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