Safety on the London Underground The earliest attack on the London Underground was in 1885, when a bomb exploded on a Metropolitan line train at Euston Square station. The Provisional IRA (and its predecessors) carried out over ten separate attacks between 1939 and 1993. As a response to growing 'Mumbai-Style' terrorist attack threats, the British Transport Police has its own detachment of armed officers who will regularly patrol both the Underground’s stations and its trains. Various regulations aim to improve safety on the Tube. Smoking was allowed in certain carriages in trains until 9 July 1984. In the middle of 1987 smoking was banned for
Urban rail in the United Kingdom and Western England. Stations within London are served by two or four trains per hour. The London Overground (often shortened to "Overground") is operated by Arriva Rail London under a concession let by Transport for London, which owns the London Underground. The Overground includes the Watford Local, North & West London, East London & South and the Gospel Oak to Barking lines. It is the only National Rail service shown on the London Underground map. All stations are served at least every 20 minutes, with stations between and on the East London Line having 16 trains per hour in each