Rail passengers across the North East will face more strike misery as part of a long-running dispute over the role of guards.
Members of the Rail, Maritime and Transport (RMT) union working for Arriva Rail North, which runs Northern's services throughout the region, will walk out on Monday, January 8, Wednesday, January 10, and Friday, January 12.
RMT members for five other rail operators will also strike across the same period.
Stations affected across the Northern route from Newcastle to Middlesbrough include Sunderland, Seaham, Hartlepool, Seaton Carew and Billingham.
The RMT fears Arriva Rail North's modernisation programme will result in the loss of 1,200 guard roles and leave both drivers and passengers isolated.
Northern, however, insists the changes will help "maintain high safety standards, deliver faster and more frequent services, more space, better stations, and staff will be more visible and available than ever before".
RMT general secretary Mick Cash said: "Every single effort that RMT has made to reach negotiated settlements in these separate disputes with the different train operating companies over safe operation and safe staffing has been kicked back in our faces and we are left with no option but to confirm a further phase of industrial action in the New Year.
"No one should be in any doubt, these disputes are about putting the safety of the travelling public before the profits of the private train companies."
But Richard Allan, Arriva Rail North's deputy managing director, said: "Northern is committed to investing in new and updated trains, better stations and faster journeys for our customers.
"Northern is still prepared to guarantee jobs and pay for conductors for the rest of our franchise to 2025 if we can reach agreement on how our colleagues deliver better customer service using those fantastic new facilities.
"Additionally, last week the Government wrote to RMT, guaranteeing employment for conductors beyond 2025 if RMT ends its dispute.
"We will be working hard to keep customers on the move during these next RMT strike days."