A man using a Vietnamese restaurant-branded car is being investigated for suspected illegal fishing, after he was confronted by an angler in the early hours of the morning.
Steve Cullen filmed the driver and two other men with a bucket of juvenile sea bass in Poole, Dorset, on Sunday.
Bass from Poole Harbour cannot be caught and kept because of low stocks.
Southern Inshore Fisheries and Conservation Authority (SIFCA) said it had launched a “full criminal inquiry”.
Mr Cullen said he was sleeping in his car at Rockley Park, Hamworthy, when he was awoken by the men at about 04:00 BST.
He said he “saw red and slung the bucket of fish back in the water” as well as taking the men’s gill-net.
In a video, posted on Facebook, Mr Cullen shouted: “It’s bass, what do you think you’re doing?”
He filmed one of the men leaving in a vehicle with the words “Eat Pho. Traditional Vietnamese Rice Noodle Soup” on the side.
A Facebook post, seemingly from the restaurant owner, apologised for his actions.
The message said: “I was not aware of the ban while doing this.
“I just decided to take our boat out after work with some friends, thinking to relax after a stressful few weeks”.
The message said bass was not on the Bournemouth restaurant’s menu.
SIFCA chief officer Rob Clark said a number of people were “helping with inquiries” and a net had been seized.
Mr Clark said Poole Harbour was a nursery area for bass, which were in a “perilous state” because of over-fishing and cold winters.
“At this time of year fishing for bass from any vessel, is prohibited. In recreational fishers, any bass caught during 2018 must be returned immediately,” he added.
The BBC has tried to contact the restaurant for comment.