As many as 80 firefighters fought a major blaze that ripped through fish and chip shops and other buildings at Southwold Harbour.
Emergency services were called to Blackshore Quay in the seaside resort at 12.50am on Monday.
Suffolk Fire and Rescue Service sent eight crews to the scene from across the county, including Lowestoft, Haverhill, Beccles, Halesworth, Woodbridge, Leiston and Wrentham.
In total, eight sheds and two fish and chip shops were affected.
One of the businesses, Mrs T's Fish and Chip Shop, posted on Facebook on Monday morning to inform customers of the incident.
The post said: "Not the news we wanted to get woken up to but unfortunately, Mrs T's has been caught in a fire on the harbour early hours of this morning.
"We are completely heartbroken.
"We want to thank the Fire team for all their hard work throughout the night to put the blaze out.
"We will keep everyone updated via our socials as soon as we know more."
Later posting on Instagram, the business said the site had been "completely destroyed".
Speaking at the site of the fire, Mel Buck, station manager at Suffolk Fire and Rescue Service, said: "We were called to the scene at 1am this morning to a fire in Ferry Road.
"On attendance we discovered several sheds and businesses were well alight.
"At the height of it, we had eight fire engines on the scene – there were about 80 firefighters here in total.
"All the crews worked extremely hard to bring the fire under control. We had some difficulties with the construction of the sheds, as well as the presence of gas cylinders.
"An investigation is now underway by Suffolk Fire and Rescue Service."
A witness staying in a nearby caravan park, who did not wish to be named, also shared their account of the incident.
They said: "We heard a bang and massive explosion – it sounded like a sonic boom.
"It must have woken the whole caravan park up.
"The smoke was probably 20 to 30 feet in the area. You could probably have seen it from all over Southwold.
"It's a really nice part of Southwold, it's such a shame."
No casualties were reported, Suffolk Fire and Rescue Service confirmed.
Ferry Road in Southwold remains closed while an investigation takes place.
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