A busy crossing over the river Yare has re-opened amid reports it had frozen shut.
Norfolk police were alerted at 2.52pm to reports Haven Bridge in Great Yarmouth had been unable to lift for a boat.
Officers were on scene preventing people from walking over the bridge and redirecting traffic.
The barriers were down at both sides.
A police spokesman said initial reports indicated the bridge was iced up and that engineers were heading to the scene.
The advice, she added, was to avoid the area if out on the roads making an essential journey.
An office worker in Hall Quay facing the bridge said traffic, although busy, was being kept moving by police but people were being prevented from walking over the bridge which was in the down position and "looked normal."
Another witness said many people were waiting to cross and traffic was backed-up.
The 90-year-old bridge has been beset by problems to do with its lifting mechanism.
Work to permanently repair it is due to start this month and take 13 weeks.
The bridge was out of action for months last year causing problems for mariners.
It re-opened at around 5pm.
A woman at the scene said it had been a tough situation with people on push bikes and mobility scooters stuck outside in the open for up to two hours.
A Norfolk County Council spokesperson, said: “Engineers have now managed to reopen the road over Haven Bridge after an attempted lift for a vessel this afternoon.
"Traffic around the town should now be starting to get back to normal after the earlier disruption caused.
"We will be investigating the issue to understand what went wrong.”
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