The RMT union has announced that Tube drivers on the Piccadilly Line will strike in a row over working conditions.
Tube cleaners and some engineers working for Transport for London will also walk out in separate disputes.
Drivers on Tube lines serving the Hammersmith and City, Metropolitan and Circle Lines voted for industrial action, short of a strike.
More top news
The organiser of a Pokemon Go meet-up in central London said he was amazed when suddenly thousands of people said they were going.
Adele surprised a fan with an accidental kiss on the lips when as she said hello at a show in Vancouver, Canada.
Jeremy Corbyn has denied allegations of bullying saying "intimidation is not allowed" in the Labour party.