Metropolitan Police are treating this as a terrorist incident and a full investigation is underway.
One of those stabbed was a member of British Transport Police responding to the incident on London Bridge. The officer received serious but not life threatening injuries. His family have been informed.
14 of those injured (six women and eight men) have been taken to King's College Hospital at Denmark Hill. One has been discharged.
Metropolitan Police have confirmed that the three attackers shot dead by armed police were pictured wearing what appeared to be explosive vests, but that these vests were not genuine.
According to South Eastern Rail trains will not stop at London Bridge station. The station and London Underground station are both closed. Trains to and from Waterloo, Waterloo East, and Charing Cross will run as usual.
Commissioner Dick has confirmed there will be additional police across the capital in the coming days, including armed officers.
A hotline for those concerned about loved ones is the Casualty Bureau on 0800 0961 233.
The current UK terror threat level remains at 'Severe', meaning an attack is expected. The threat level is set by the Joint Terrorism Analysis Centre.
The major political parties have suspended their election campaigns, with the exception of Ukip. Several election focused TV programmes on the BBC have been cancelled.
Prime Minister Theresa May is meeting with the COBR committee on Sunday morning, which responds to major incidents.
The identity of the attackers and victims is currently undisclosed.
Update: Just after 10.30am the Prime Minister made a statement outside of Downing Street. In addition to confirming the information already released by the Metropolitan Police and emergency services, the Prime Minister repeatedly said:
Things cannot go on as they are.
In addition May connected the attack at London Bridge to the recent attacks at the Manchester Arena and the Westminster Bridge attack. May said that:
The attacks are not connected by common networks but are bound together by the evil ideology of Islamist extremism...It is an ideology that is a perversion of Islam and a perversion of the truth.
May called for greater regulation of cyberspace to prevent terrorism, through domestic regulation and international co-operation on the issue.
The government will review its counter terrorism strategy, and will consider increasing the length of custodial sentences for terrorist offences.
The UK must say "enough is enough" and have "difficult and embarrassing" conversations about extremism.
The general election on Thursday will go ahead as planned. Campaigning will resume on Monday.