Horrific scenes are being described in London - as it emerges that armed police shot dead three attackers from last night's London Bridge rampage.

The attack left six people dead and 48 injured.

Londoners were urged by police to "run, hide, tell," if they were caught up in the chaos of the evening.

According to the BBC, the three men shouted "this is for Allah," before they mounted the pavement and mowed down 20 people in a white van travelling at 80km/h on London Bridge.

#Londonbridge #boroughmarket #vauxhall pic.twitter.com/a7OciBEBjH

— Metropolitan Police (@metpoliceuk) June 3, 2017

Using 30cm-long hunting knives, the attackers then stabbed a police officer before turning their attentions to those in nearby bars and restaurants at Borough Market.

One man was reportedly stabbed five times in the chest; another was stabbed three times. There are further reports of individuals having their throats cut.

Whatever the United States can do to help out in London and the U. K., we will be there - WE ARE WITH YOU. GOD BLESS!

— Donald J. Trump (@realDonaldTrump) June 3, 2017

The injured police officer is currently being treated for serious head, leg, and face wounds.

London Ambulance Service has confirmed this morning that it took 48 people to five different London hospitals.

My statement on the cowardly terrorist attack in London tonight: https://t.co/PaGXogN60N Please continue to follow @metpoliceuk for updates pic.twitter.com/AcGaju2Svp

— Mayor of London (@MayorofLondon) June 4, 2017

Photographs and video footage appear to show at least one of the men with metal canisters strapped to his bodies - though this 'suicide vest' was later said to be a dummy. The men were shot dead at 10.16pm; just eight minutes after beginning their attack.

This morning, armed law enforcement are sweeping the area as the investigation continues. Counter Terrorism Command stated: "We are reviewing and planning to strengthen our policing stance across London over the forthcoming days, and there will be additional police and officers deployed across the Capital."

[caption id="" align="aligncenter" width="722"] Photograph: Dominic Lipinski/PA[/caption]

Gerard Vowls was in a pub near London Bridge and said he threw chairs and glasses at the attackers. He told The Guardian: "They kept coming to try to stab me - they were stabbing everyone. Evil, evil people."

Another man in conversation with DailyMail.com described how he was in a pub by the Shard: "I was feet away from getting stabbed," he explained. "Saw so many people literally dying. Was in a pub and they were at the door stabbing people.

We have taken 48 patients to hospital following the incident at #LondonBridge https://t.co/hCiKVCBrnb pic.twitter.com/5ipl5vtcTB

— London Ambulance (@Ldn_Ambulance) June 4, 2017

Photographer Gabriele Sciotto was watching the Champions League Final nearby. He told BBC News: "I noticed this man with this kind of explosive looking belt on his chest, they were running," he said.

"A police officer was trying to put himself between them and the crowd. After that they were almost coming towards me and I tried to run away."

He continued: "More police came over, I guess they were on radio or something because in around like two or five seconds they shot all the three men down."

London bridge bar now. Police everywhere pic.twitter.com/0gWH9jhgdX

— James Yates (@Yatesy17) June 3, 2017

One frightening video circulated widely on Twitter also shows people in the basement bar Katzenjammers hiding under tables.

Mayor of London Sadiq Khan described the events as a "deliberate and cowardly attack on innocent Londoners and visitors to our city enjoying their Saturday night". Prime Minister Theresa May: "Our thoughts are with those who are caught up in these dreadful events."

Terrible news coming from London - we stand with our close neighbours again tonight. @IrelandEmbGB monitoring the situation.

— Enda Kenny (@EndaKennyTD) June 3, 2017

Enda Kenny stated that Ireland was standing with "our close neighbours again". The Irish embassy in London confirmed it was monitoring the situation. The US State Department said it "condemns the cowardly attacks targeting innocent civilians in London," while French President Emmanuel Macron said his country was "at the side of the United Kingdom". Ariana Grande, who tonight plays a charity concert in Manchester following the fatal terrorism attack at her gig there on May 22, also tweeted her supported, saying that she was "praying for London".