Twelve people were arrested in counterterrorism raids in the Barking area of east London, police said on Sunday.
A woman has been described as "heroic" after she reportedly used her body to barricade the door of a restaurant in the London Bridge area, stalling terrorists trying to enter during Saturday night's attacks and possibly saving the lives of up to 20 people.
In response to the London attacks, the State Department issued a statement condemning them as "cowardly".
In a gruesome attack, 7 people were killed after three knife-wielding attackers in fake suicide attacked British capital, plowing a van into pedestrians on the iconic London Bridge and stabbing revellers in a nearby market.
The focus on cybersecurity was critical, he said. "We need to ask where it's going next", he said. "I hid in a restaurant basement for about an hour. Therefore, I refuse to suspend campaigning because this is precisely what the extremists would want us to do".
She said the attackers were bound by the "evil ideology of Islamist extremism" which was a perversion of Islam, and defeating this ideology was one of the greatest challenges of our time.
Donald Trump berates London mayor for terror attack statement that never was
At least four police vans were stationed behind a cordon outside the Elizabeth Fry flats in King's Road. "My thoughts go out to the victims and their loved ones", said French President Emmanuel Macron.
British Prime Minister Theresa May, who faces an election on Thursday, called for tougher counter-terrorism measures after the country's third major attack in two months, and declared "Enough is enough".
Ms Dick said police have "very good" resources and "extraordinarily highly-trained people" but attacks are hard to predict.
Saturday's attacks bore similarities to one in March on Westminster Bridge in London, in which a man plowed into a crowd of pedestrians, killing five, and then stabbed a police officer to death in the grounds of parliament before being shot dead.
He said: "I saw that man with a knife in his hand and after that a man started screaming so I knew something wrong was happening". The first instance of violence was reported at 10:08 PM (local time) from London Bridge, where a fast-moving van moved down civilians standing over the pavement.
The vehicle stopped near Borough Market, a neighborhood filled with bars, restaurants and tourists.
Assistant Commissioner Mark Rowley, the Metropolitan Police head of counterterrorism, said that while police believe all the attackers were killed, the investigation is expanding. Her office said she would chair a meeting of the government's COBRA emergency committee on Sunday.
Neighbours report hearing shots as 12 are arrested in raid on flats
At least four police vans were seen stationed behind a cordon outside the Elizabeth Fry flats in King's Road, Barking. He said he threw chairs, glasses and bottles at the attackers in a bid to stop them.
World leaders were quick to condemn the attacks.
The police ordered him to join a throng of people being evacuated from a nearby pub.
He told the Press Association: "Then someone came in off the street and he had a white cuff around his neck".
Following the attack, political campaigning in the country has been suspended by both - Labour and Tories on Sunday, in wake of the terror attack.
The threat level was last weekend lowered to the second highest category of severe, meaning an attack was judged "highly likely".
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Mr Trump and his entourage arrived at the Vatican just before 8:30am, in a meeting that was arranged at the last minute. The pope had presented Trump with a medallion engraved with an olive tree, the worldwide symbol of peace.