Hundreds of thousands of train commuters in London and southern England are facing misery as rail staff begin a five-day strike in a row over who opens and closes the doors.
Southern, which runs trains from destinations such as Brighton and Gatwick Airport, has said only 60 percent of its services would operate during the week-long stoppage, the longest British rail walkout for almost 50 years, and no trains would operate at all on some routes.
The latest disruption provides further disruption for wearied passengers who have suffered months of cancellations and delays because of high levels of staff sickness while in July Southern axed 341 trains, about 15 percent, to provide what it said would be a more regular service.
The dispute centres on the role of conductors, staff who current have responsibility for opening and closing the train doors. The RMT union, one of Britain's most militant, says Southern want to extend the use of driver-only operated trains and so reduce the safety role the conductors provide.
Govia Thameslink Railway (GTR), Britain's largest train operator which owns Southern, says the changes would lead to fewer train cancellations as services would no longer require both drivers and conductors.
"Our fight is with the company and the government who have dragged this franchise into total meltdown," said RMT General Secretary Mick Cash.
"We share the anger and frustration of passengers and we cannot sit back while jobs and safety are compromised on these dangerously overcrowded trains."
During mediation talks last week, the union said it had offered to call off the strike if GTR had promised there would be a second staff member on trains while negotiations continued.
However, the talks failed as GTR said in times of disruption, there might be occasions when they would let trains run with just a driver.
The company's chief executive Charles Horton said their planned changes would improve services for passengers and had provided guarantees about the future role of conductors but the RMT had refused to negotiate.
"The RMT union is letting everyone down and the action they are taking this week is unnecessary, unacceptable and unjustified," he told BBC radio.