Police have confirmed the London Bridge and Borough Market incidents were terror attacks, the third to hit the UK in less than three months following the Westminster and Manchester atrocities in March and May.

Seven people have died and at least 48 are being treated in hospitals across the capital after a van ploughed into pedestrians on the bridge, followed by a series of stabbings around Borough Market on Saturday night.

Scotland Yard said three attackers were shot dead by armed officers.

As the emergency unfolded, from around 10pm last night, the Met issued a message urging members of the public in the affected areas to 'run, hide and tell'.

The guidance was prepared by counter-terrorism police to set out the steps people should follow in the event of an attack.

An on-duty British Transport Police officer received 'serious injuries' including head, face and leg wounds, as he responded to calls for help from the public, Scotland Yard said.

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London Ambulance Service said: 'We can confirm we have taken at least 20 patients to six hospitals across London following the incident at London Bridge.

'We have also treated a number of people at the scene for less serious injuries.

'We have declared a major incident and continue to work closely with other members of the emergency services.

'Our priority is to ensure patients receive the medical help they need as quickly as possible.'

An eyewitness by the name of Gerard described the series of stabbings by three men near Borough Market.

'They were stabbing everyone. They were running up and going 'This is for Allah',' he told BBC News.

'They run up and stabbed this girl - I don't know how many times - 10 times, maybe 15 times.

'She was going, 'Help me, help me' and I couldn't do nothing. I threw something - there was a bike on the floor. I threw something at them like a bike or a chair.'

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Emergency services were seen treating people lying injured at the junction of Thrale Street and Southwark Street, near Borough Market.

An image shared by a photographer on social media showed a man on the ground with what appeared to be grey canisters around his waist by the Wheatsheaf pub in Borough. He told the BBC he saw three men shot by police.

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Explosions, believed to be controlled, have since been heard in the London Bridge area.

A third incident involving a stabbing at Vauxhall was unrelated, the force added.

Prime Minister Theresa May said she was being updated by officials on the 'fast-moving' situation and thanked the emergency services, adding: 'Our thoughts are with those who are caught up in these dreadful events.'

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She will chair a meeting of the Government's Cobra emergency committee on Sunday, No 10 said.

Scotland Yard said officers were responding to three incidents in the capital.

After the bombing in Manchester, the official terror threat level was raised to the highest - critical - amid fears further attacks could be imminent.

It was the first time the assessment had reached the most serious rating for nearly a decade and a huge security response was activated, with military personnel drafted in to support police.

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Last weekend the threat level was lowered to the second highest category of severe, meaning an attack was judged 'highly likely'.

It was revealed following the Manchester blast that security services had foiled 18 plots in Britain since 2013, including five since the Westminster attack.

The threat being confronted by the UK's counter-terrorism agencies is seen as unprecedented, with 500 active investigations involving 3,000 subjects of interest at any one time.

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Here is what we know following the incident at London Bridge and Borough Market

• Seven people have died after terror attacks struck London on Saturday night.

• Three male suspects were shot and killed in Borough Market.

• The men were wearing what looked like explosive vests but these were later found to be hoaxes.

• More than 48 patients have been taken to five hospitals across London.

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• Police were called at around 10.08pm to reports of a vehicle hitting pedestrians on London Bridge.

• Officers then attended a second incident at nearby Borough Market after reports of stabbings.

• Both incidents were declared by the Metropolitan Police as 'terrorist incidents' at 12.25am on Sunday.

• A third incident at Vauxhall was a stabbing and unrelated, Scotland Yard said.

• Prime Minister Theresa May is returning to Downing Street to receive further briefings from security officials.

• The Prime Minister will chair a meeting of the Government's Cobra emergency committee on Sunday.

The Met said its Casualty Bureau was open and urged those worried about their friends or relatives to call 0800 096 1233 and 020 7158 0197.

Among the injured are:

• A British Transport Police (BTP) officer and an off-duty Metropolitan Police officer are in hospital with serious injuries but neither are believed to be in a life-threatening condition, Scotland Yard said. The BTP officer, who was on duty, was one of the first to the scene after he responded to calls for help from the public, the force said.

He suffered serious injuries when he was stabbed in the face, head and leg, wounds which BTP said are not thought to be life-threatening.

• New Zealander Oliver Dowling is reported to have been left in a coma after being stabbed in the face, neck and stomach.

Mr Dowling, 32, from Christchurch, is said to have had four hours of surgery for his injuries and is an induced coma.

According to the Mirror, his sister Freddy Dowling said on Facebook: 'Doctors are very happy with how he's come out the other side. A massive thank to the University of London Hospital for their tireless efforts in helping my brother out.'

It was reported his girlfriend, Marie Bondeville, was also injured.

• Sunday Express business editor Geoff Ho was left in intensive care after being stabbed in the throat when he tried to help a wounded bouncer.

Mr Ho was filmed being led away from the scene by a policeman, clutching his neck and with his shirt off.

According to the Mirror, he wrote on Facebook: 'Don't know whether it was stupid or noble to jump in and break up the fight outside the Southwark Tavern, but two a***s trying to do over the lone bouncer on the door isn't happening on my watch.'

Friend Isabelle Oderberg tweeted: 'We have found Geoff. He is in intensive care.' She told Melbourne newspaper The Age: 'He is actually a martial artist and I wouldn't be surprised if he would have stood up and been counted because he's just that type of person.'

• Australian woman Candice Hedge is reported to be one of two Australians injured. The Courier Mail newspaper reported that she was stabbed in the neck while eating dinner with her boyfriend after finishing a shift at Elliot's restaurant in London Bridge.

The paper reported that the 31-year-old had her throat slashed after a man grabbed her from behind.

She reportedly wrote on Facebook: 'Hey everyone, just so you know im doing ok. Bit of pain but I will survive. Thanks for your thoughts and well wishes. Love to all.'

• Canadian authorities said one of its citizens was 'directly affected' by the attack, and that consular officials are offering support.