A man has described the moment a cruiser sped through the water on the Norfolk Broads causing a large wave to crash into his boat and smash some of his possessions.
Carl Brice, 47, said his daughter Kiera, five, who was on board at the time of the incident, was now too scared to go back on it.
Kiera and her sister Mia, seven, were in bed and Mr Brice was watching TV when he heard a boat roaring down the River Yare generating a wave of water at around 10.30pm on Saturday.
He said: "The wave really was very big and I just braced myself for impact by jumping to the floor. It was terrifying.
"The boat wouldn't stop rocking and the breakfast bowls I'd set up for the morning were completely smashed. The girls' toys went everywhere and the TV was knocked off its hinges."
The Broads Authority confirmed it was investigating the incident and it would take "robust" action against those responsible.
Lifeboat crews from Hemsby launched from Reedham Ferry and went to Brundall to assist any craft affected in the incident.
They were joined by members of the Gorleston and Winterton coastguard teams which helped in the aftermath.
Hemsby lifeboat member Daniel Hurd described Saturday's events as a "complete waste of resources".
Mr Brice said his daughters were shaken up by the incident and were not able to get back to sleep until 1am.
"Kiera didn't want to be on the boat the following day and is now scared to be on board again," he said.
"The people who did this are mindless morons. I just hope they get caught."
He has been spending his holidays on boats for 40 years but has been living on the River Yare permanently for almost two years.
He said: "I've never seen anything like it. A number of other boats were affected but I think I caught the brunt of it.
"Everyone was shocked in the morning that this had happened."
Mr Brice said he would contact his insurance company as he sought compensation for the damages.
? If you witnessed the incident or have any evidence that you feel will be beneficial to the investigation call Broads Control on 01603 756056.
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