Some 600 highly trained marksmen began patrolling the streets of London on Wednesday, as the Metropolitan Police increased both its force and visibility to protect Britons from “all manner of threats,” said Scotland Yard Commissioner Sir Bernard Hogan-Howe. He has in the past warned that a terror attack in Britain was a matter of “when, not if,” and the officers will wear body armor and carry automatic assault rifles, Tasers, and sniper rifles. These response teams will be able to “operate on water, and to abseil down onto buildings,” the Evening Standard reported. The city—and all of Britain—is known for a police force that, for the most part, does not carry firearms. Even with Wednesday’s extra officers, 31,000 police will remain unarmed.