Workers in one of the rail operators hit by disruption to services are to stage a series of fresh strikes in the long-running dispute over the role of guards.
Members of the Rail, Maritime and Transport union on Arriva Rail North (Northern) will walk out for 24 hours on June 19, 21 and 23.
The company has been under fire in recent weeks because of daily delays and cancellations to rail services.
RMT general secretary Mick Cash said: "We have seen over the past fortnight that Northern is a company which has declared war on its passengers and staff alike.
"RMT will not stand aside while the threat to axe safety critical guards from Northern services remains central to the company plans.
"This company has reduced the timetable to total chaos and the union will not allow them to slash the safety culture to ribbons in the same fashion.
"It is a tribute to the determination and professionalism of RMT members on Arriva Rail North that they have remained rock solid for over a year now in what is a clear-cut battle to put public safety before private profit.
"German-owned Northern Rail want to run half a million trains a year without a safety critical guard on board in a move that would wreck both safety and access to services and they should listen to their front-line staff and pull back from that plan immediately.
"RMT has agreed arrangements in Wales and Scotland that enshrine the guard guarantee. If it's good enough for Wales and Scotland to have safe rail services it should be good enough for the rest of Britain."