London Bridge Attackers

The investigation into this horrific attack is fast moving and complex as we piece together a fuller picture of what occurred. So far officers have arrested 12 people – seven women and five men - and searched six properties (four on Sunday and a further two properties today). One of the arrested men and one of the women were subsequently released.

"Counter terrorism partners have dedicated intensive effort to developing and improving our counter terrorism response over recent years, as the threat has changed. The more we know, the greater the chance when an attack does happen we will have some information about at least one perpetrator. Our work necessarily involves making difficult judgments about how to prioritize the resources available to us at a time when the UK is facing a SEVERE and high tempo terrorist threat.

"There are 500 current terrorism investigations, involving 3,000 current subjects of interest. A small number of the highest priority investigations involve current attack planning, and these investigations command a significant proportion of our resource. The remainder of our investigations focus on other activities relating to active support or facilitation of terrorism.

"Khuram Shazad Butt was known to the police and MI5. However, there was no intelligence to suggest that this attack was being planned and the investigation had been prioritized accordingly. The other named man, Rachid Redouane, was not known.