Almost 200 Stagecoach bus drivers in Sunderland walked out on Saturday 5 November in protest at what unions describe as "poverty pay".
It is the seventh day of industrial action after the GMB union members rejected a 4% pay rise with a further 2% to follow later on.
Workers claim that would be a real-terms pay cut, but Stagecoach said its pay offer would make them some of the region's highest paid drivers.
Stuart Gilhespy, GMB organiser, said: "Stagecoach keeps saying they want to negotiate, but whenever we try and talk to them, they refuse to change their offer. That's not a negotiation.
"No one wants this strike, least of all the drivers who are suffering financially. It means the world that their community - the people of Sunderland - are backing them in this dispute as they try to make ends meet."
A Stagecoach North East spokesperson said the industrial action is having a "significant impact on communities in Sunderland".
The spokesperson added: "Drivers in Sunderland have been offered a pay deal which is higher than local competitors and would make GMB union members amongst the highest paid bus drivers in the region.
"Throughout our discussions, we have demonstrated our total commitment to reaching a realistic agreement with GMB and would urge them to return to talks."
There are further Stagecoach driver strikes set for 15-19 November, 23-24 December and 26-27 December.
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