Thousands of London commuters faced travel chaos today when a major tube line was suspended because of a 24-hour strike by workers. Members of the Rail Maritime and Transport Workers' (RMT) union based on the Victoria line walked out at 9pm last night over a dispute about the safety of the sliding-door opening mechanisms as well as the sacking of a train driver and the alleged victimiation of a union activist.

The action, which the union said was "solidly supported", led to the suspension of the entire line today, forcing commuters who use the line, which runs from Brixton in the south to Walthamstow in the north-west of the capital, to seek other transport.

In a statement the RMT said the management of London Underground "refused last minute talks to resolve the dispute over passenger door safety and the bullying and victimisation of RMT members".

RMT said it had a dossier of 18 incidents over the last four years when doors on the wrong side have been opened on the Victoria line, posing a serious safety risk to the public.

"If the doors open incorrectly, and you or your kids are jammed into the carriage, the potential for a tragedy is clear, and that's why every other line on the underground has brought in this fail-safe mechanism," Bob Crow, the RMT general secretary, said today.

Tickets were being accepted on buses and overground trains, but the strike was attacked by business groups, while Transport for London said the action was "completely unnecessary".