London Underground staff vote for industrial action
London Underground office staff have voted for industrial action in a row over ticket office closures.
Nearly 68% of members of the Transport Salaried Staffs' Association voted for strikes on a 44% turnout.
The Union has said its members had been subjected to "unprecedented" levels of abuse since ticket offices closed.
A survey for the TSSA found most staff felt less safe since moving from offices on to station concourses.
Tom Edwards, BBC London Transport Correspondent
The ticket office closures were one of the biggest changes on the tube for generations.
With the rise of automatic payments methods such as the Oyster card and contactless, the idea was to get staff from behind the glass screens and on to the ticket gate lines. But the unions have always opposed it and say the redeployment has led to more lone working and staff shortages.
The TSSA, which represents station staff, says it will decide, probably tomorrow, what industrial action it will take in the dispute.
Strikes aren't being ruled out, although it could be an overtime ban.
Other forms of industrial action were backed by nine to one.
The union said staff were being targeted by frustrated passengers if ticket machines do not work.
TSSA general secretary Manuel Cortes said the vote was about "our members being prepared to take part in a strike to let the world know that the Tube they are using is not fit for safe purpose".
"Our customer service assistants are overwhelmingly trying to warn the public that the Tube they use is not safe. We no longer have enough staff," he said.
Steve Griffiths, London Underground's chief operating officer, said: "We urge the TSSA leadership to work with us constructively on the issues they have raised rather than threaten to disrupt our customers with strikes. "
The ticket offices were closed as part of the Fit for the Future programme introduced by former London mayor Boris Johnson.
His successor Sadiq Khan has ordered a review of the project.
Tube drivers are to stage 24-hour strikes on 6 and 7 December, coinciding with a walkout by Southern Rail guards.