Remain supporters on the bank and on the bridges jeered the passing Brexit vessels
The campaigns for the European Union referendum took a turn for the bizarre when a flotilla of boats from both sides clashed on the River Thames.
Nigel Farage and Leave supporters joined trawlers sailing past the Houses of Parliament in a protest over EU fishing policies.
Meanwhile Bob Geldof - on one of the Remain boats - used a loudspeaker to declare that the UKIP leader should be "ashamed of himself".
The musician and activist added: "You're a fraud Nigel, go back down the river because you're up one without a canoe or a paddle."
The Brexit vessels - many of them small fishing boats - blasted their foghorns as they passed under Tower Bridge.
But pro-EU boats headed out to intercept the flotilla, 'In' flags fluttering and pumping out songs such as In With The In Crowd and Chicago's If You Leave Me Now.
Remain supporters on the bank and on the bridges jeered the passing Brexit vessels, which carried banners reading "The Only Way is Brexit".
Some Remain craft were reportedly fired upon with water from a fishing boat's hose and a police boat kept close watch as the rival vessels squared up to one another.
Mr Farage - who waved to supporters from the deck of one of the boats - attacked the EU's Common Fisheries Policy (CFP) which he said had "devastated" the UK's fishing industry and led to the loss of tens of thousands of jobs.
Mr Farage said he wanted the fishing issue to be a "bigger part" of the debate as the days count down to the big vote.
He also criticised the Remain vessels and "upper-middle class types and multi-millionaires" for trying to "shout down" the fishing boat flotilla.
Aaron Brown, a founding member of the group Fishing for Leave, said Geldof's protest was "disgusting".
Mr Brown, a fisherman who had travelled down from Ayrshire, argued that Geldof had never been in a fishing boat and that he was "decrying and shouting down working fishermen".
But Greenpeace has accused Mr Farage of "cynical opportunism" with the river demonstration.
It said that in more than three years on the European Parliament's fisheries committee he had attended just one of more than 40 meetings and failed to vote on three significant measures designed to improve the CFP.
Greenpeace UK executive director John Sauven said: "When Nigel Farage had a chance to stand up for UK fishermen in Brussels, he bunked off.
"His no-show voting record proves he's no fisherman's friend but a cynical opportunist exploiting the harsh predicament of many fishermen for political gain."
When asked about the claims, Mr Farage told Sky News he had "no idea" how many of the meetings he had attended.
"One out of 43, one out of 430, it's irrelevant - we can't change anything. This is written into the treaties," said the UKIP leader.