You might be surprised, the Special Patrol Groups could hold their own against most SWAT teams, but they never pussied about 'negotiating', they beat the heck out of everyone and sorted out the bodies afterwards.
You'll see them with MP5's at the airport, and every constabulary has armed patrols out on the streets.
My cousin was a commander at Scotland Yard and he has some very interesting stories. I dated a scene of crime officer as well, you'd be surprised how many murder scenes she attended in a month.
"Special" Patrol Groups carry MP5's at airports. Our regular uniformed officers carrying just a sidearm can do that. "They beat the heck out of everyone" because most everyone over there is a cowering WIMP...except for their beloved terrorist they just can't seem to get enough of