Forgot NI Lewis? Surely the largest armed UK police service is the PSNI..?
>(the largest armed police command in the UK is the Metropolitan Police Diplomatic Protection Group, with 700 officers who are mainly employed guarding embassies).
According to wikipedia (in 2011) the PNSI has 7200 officers with 2500 of them being backroom staff.
"Due to the elevated threat level police personnel face from armed paramilitary groups, unlike the majority of police services in the United Kingdom, the PSNI routinely arms all of its officers with firearms and allows its officers to carry their issue sidearm off-duty."