One of the groups campaigning for Britain to leave the European Union created a fake company so two protesters could heckle David Cameron during his key speech to business leaders.
The pair of students interrupted the Prime Minister as he addressed the pro-Confederation of British Industry by holding up banners and chanting: "CBI: voice of Britain".
Vote Leave was behind the stunt, setting up the Lyon Shepphard Web Solutions website and registering it as a company so the two youngsters could be granted access to the CBI's conference in central London.
The two 19-year-olds, Peter Lyon and Phil Sheppard, are members of Students for Britain, which is campaigning for "fundamental reform of Britain's relationship with the European Union".
Pro-EU campaigners dismissed the protest as "grubby" and said Vote Leave had serious questions to answer over their decision to set up a fake company.
Mr Cameron remained unflustered during the protest, telling the pair of protesters "stop making fools of yourselves".
Mr Lyon told Sky News afterwards that it was "one of the most terrifying things I've done in my life".
"We're worried about the CBI misrepresenting British businesses' views," he said.
"We don't want the British public to be swayed by the CBI making claims about the views of British businesses when in reality a lot of particularly small and medium-sized businesses in the UK feel that the EU hinders rather than helps them."
Explaining how they managed to gain access to the conference, Mr Sheppard said: "We got in because Vote Leave formed a company for us that was able to get us in and we managed to get our passes and we pretended to be bussinessmen."
Eurosceptic Tory MPs
Eurosceptic Tory MPs
1/7 Owen Paterson
Formerly a cabinet minister, Owen Paterson is now free to make his opinion known on the backbenchers. On the subject of Europe, he does so regularly – claiming recently that the EU referendum was “rigged” in favour of staying in
2/7 John Redwood
A longstanding eurosceptic, Mr Redwood warned last year that businesses that spoke out in favour of EU membership would be punished at the check-outs by anti-EU
3/7 Bill Cash
Awkward squad rebel Bill Cash said last year that he thought the EU had become an undemocratic, German-dominated project. “An increasingly assertive German Europe is at odds with British national interests,” he wrote in the Daily Telegraph
4/7 Philip Davies
From the Conservative party’s hard right wing, Philip Davies has been a longstanding critic of the EU. He founded the Better off Out campaign and is so eurosceptic that Ukip decided not to stand a candidate against him in 2010 because they agreed with him
5/7 Nadine Dorries
Outspoken Tory MP Nadine Dorries has previously advocated an alliance with Ukip. At the height of the Greek crisis in 2013 she said that the EU was “dying on its feet”
6/7 Liam Fox
The former defence secretary is a central figure on the right wing of the Conservative party. He’s long put pressure on David Cameron over EU negotiations
7/7 Zac Goldsmith
A socially liberal eurosceptic, Goldsmith was one of the founding members of the People’s Pledge campaign to get MPs to sign up for an EU referendum. His father ran the Referendum Party, a precursor to Ukip
Responding to the protest, a spokesman from the rival Britain Stronger in Europe said: “This grubby protest from Vote Leave is a sign of how desperate Vote Leave have already become. Vote Leave will now face serious questions about the conduct of their campaign, and must clarify if indeed they created a fake company in order to disrupt this event.”
However the Conservative MEP Daniel Hannan defended the protests, saying they were raising "a legitimate point" and dismissed suggestions that organisers of the stunt behaved in a fraudulent way.
"As the students said, the CBI, which is Brussels funded, has been consistently wrong about the EU," Mr Hannan told Sky News. "It’s never ever deviated its support for ever closer integration and it isn’t the voice of business. As they were saying, it’s the voice of Brussels not the voice of business.
"It’s a democracy and people are free to make a point and I think the much bigger issue is the point that they were making," he added.