The majority of the 100 extra officers will be of constable rank, and the unit will lose Det Ch Supt Duthie, who will become head of homicide next month, and one superintendent.
He stressed that officers will retain their specialisms in terms of the types of crime they investigate.
"This is a high-risk area and we need to make sure that we've got the right people with the right training."There would be a danger if we were to use 'omnicompetent' officers. But we've made a conscious decision that this is a high-risk area, we need to have dedicated officers investigating dedicated types of crime."
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A man has died and two others have been injured in a stabbing outside Parsons Green Tube station.
Dany Cotton says referring to 'firemen' reinforces the stereotype that only men want to work in the fire service.
His heart completely stopped and one of his teammates performed CPR until paramedics arrived.