A bit of perspective;
Murder rates:
Honduras (2008) 57.9 per 100,000
USA (2008) 5.8
England & Wales (2006) 1.37
Japan (2005) 0.64
Baltimore (pop. c. 637,000)
2006 = 276 homicides (43 per 100,000)
2007 = 282 homicides (44 per 100,000)
2008 = 234 homicides (37 per 100,000)
(Detroit and New Orleans also have very high rates)
Lambeth (pop. c. 272,000)
2006 = 14 homicides (5 per 100,000)
2007 = 23 homicides (8 per 100,000)
2008 = 15 ??? homicides (5 per 100,000)
The study that ranked Nottingham and St Helens as having the highest UK murder rates (5.21 and 4.87 per 100,000) didn't calculate rates London boroughs separately, so the lower crime outer London boroughs 'covered up' for the higher crime inner London ones.
If Lambeth was as bad as Baltimore it would have about 120 murders per year or 1 every 3 days.