Gerard Vowls said he shouted “oi cowards” before launching pint glasses and stools at the three men, who were stabbing people in Borough Market.
The man said he was trying to get the men to chase him in order to lead them to police following the London terror attack on Saturday night.
It happened after they mowed down pedestrians on London Bridge before stabbing passers-by on foot, killing at seven people and injuring 48.
He told Sky News: “I threw a bottle, I think I chucked a stool, pint glasses because I thought ‘the police are going the wrong way’.
Eyewitness Gerard Vowls said he throw bottles at the suspects
They stabbed a bloke, he went on the floor, they stabbed a woman in there – I thought ‘I’ve got to do something’
“I could hear them going straight past, going to where it first happened but they [the attackers] had already left that scene.
“They were in the market and they were attacking people in there and I was going ‘lock the doors or get out, they’re coming in to stab you, they’re stabbing everyone, they’re terrorists’.”
He said he then saw the suspects stabbing a man and a woman at the Wheatsheaf pub.
“They stabbed a bloke, he went on the floor, they stabbed a woman in there – I thought ‘I’ve got to do something’,” he said.
London terror raids Sun, June 4, 2017
Police have raided a block of flats in Barking in connection with last night's London Bridge terror attack.
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As police continue their investigations following the June 3 terror attacks, a block of flats in Barking is raided for possible suspects
Armed police have been patrolling in London
“I thought if I throw bottles or chairs at them they’re going to want to come after me, so I thought if they chase me I can get them to the main road where the police are and they can see them [the attackers] and they can shoot them.”
The three men were soon shot dead by police following an eight-minute rampage.
Prime Minister Theresa May has since issued a statement on the attack saying “enough is enough” after the country suffered the third terror attack in three months.
In a statement, she said: "There has been far too much tolerance of extremism across society," adding that the country needed to come together for a "one truly United Kingdom".