London: Bus drivers are to be issued with DNA kits so that passengers who spit on them can be traced by police. The "spit kits" are already supplied at all 275 Tube stations and are expected to be rolled out this summer across London's 7,000-strong bus fleet. It is the latest initiative against anti-social behaviour on buses and has coincided with the Mayor's introduction of free bus travel for under-16s. The DNA kits will allow drivers to take swabs of saliva that can be passed to the police and checked against criminal records. Transport for London says that about seven...