A journalist has invited any Isis terrorist to a sword duel for a £50,000 reward on his own head after seven people were killed in the attack on London Bridge.

Andre Walker, a New York Observer columnist, posted a photo of himself on the Westminster terrace by the Thames, holding what appeared to be a sword with both hands.

“A bounty on my head. Any #ISIS terrorist that kills me gets £50k. I'll give my address. No police. But I've got a sword. Good luck,” he tweeted.

London terror attack: What we know so far

He added: "I'm not worried about looking silly, nor am I worried about #ISIS... Come on lads, have a crack."

The reaction to the tweets was mixed, with some people on social media engaging in humour while others criticised the post for its timing.

“Not sure what point you're making with this,” one person commented.

“So let's get this straight. You're offering to fund terrorism?” another person asked.

A third said: “Probably illegal to carry a sword around in the street like that. This is the dumbest thing I've seen on twitter so far this morning.”

Mr Walker said the reason for his offer was “very simple”.

“[…] fight someone who is a fair opponent. No honour in running over children,” he responded online.

The social media post comes hours after seven people were killed and 48 injured in the third terrorist attack in the UK since March.

"As a Mancunian I was devastated about the terror attack at Manchester Arena," Mr Walker told The Independent. "These cowards want to blow up little girls, and run over tourists.

"As a freeman of the City of London I have a sword. And my offer to any terrorist is this: why don't you pick on someone your own size."

London Bridge Terror Attack Show all 16 1 /16 London Bridge Terror Attack London Bridge Terror Attack Armed police on Borough High Street as police are dealing with a "major incident" at London Bridge PA London Bridge Terror Attack Armed Police talk to members of the public outside London Bridge Hospital as police are dealing with a "major incident" at London Bridge PA London Bridge Terror Attack Police Officers outside the Barrowboy and Banker Public House on Borough High Street as police are dealing with a "major incident" at London Bridge PA London Bridge Terror Attack Armed Police talk to members of the public outside London Bridge Hospital as police are dealing with a "major incident" at London Bridge PA London Bridge Terror Attack Armed police on Borough High Street as police deal with a 'major incident' at London Bridge PA London Bridge Terror Attack Emergency services near the scene of the incident Screengrab London Bridge Terror Attack People run down Borough High Street as police are dealing with a "major incident" at London Bridge Reuters London Bridge Terror Attack Emergency services arrive at the scene near Borough market at London Bridge Carl Court/Getty Images London Bridge Terror Attack Emergency personnel on London Bridge as police are dealing with a "major incident" at London Bridge PA London Bridge Terror Attack Police sniffer dogs on London Bridge as police are dealing with a "major incident" at London Bridge PA London Bridge Terror Attack A second helicopter lands on London Bridge as police are responding to three incidents in the capital, amid reports that a vehicle collided with pedestrians on London Bridge, Scotland Yard said. Officers are dealing with reports of stabbings in Borough Market, where armed officers attended and shots were fired. They are also at an incident in the Vauxhall area PA London Bridge Terror Attack Police attend to an incident on London Bridge in London REUTERS London Bridge Terror Attack Police attend to an incident on London Bridge in London, Britain Reuters London Bridge Terror Attack A police officer escorts members of the public to safety at London Bridge Getty Images London Bridge Terror Attack Police attend to an incident on London Bridge in London, Britain Reuters London Bridge Terror Attack Police attend to an incident near London Bridge in London, Britain Reuters

Three male suspects were shot and killed within eight minutes of the first call to emergency services just after 10pm on Saturday evening.

The men had rented a white van and ploughed into bystanders on London Bridge, before exiting the vehicle and randomly stabbing people in pubs and bars near Borough Market.

Many people were rushed to hospital and remain in critical condition.

On social media, members of the public and politicians vowed not to be divided by terrorism.

Main political parties said they would suspend their campaigns.

The Manchester Arena concert, in honour of the 22 victims who were killed in an explosion last month, will go ahead on Sunday.

People responded negatively to a CNN report that the streets around London Bridge remained “eerily quiet”, and a New York Times headline which claimed the city was still “reeling” after the attack in Manchester.