South Western Railway and Eurostar rail workers begin strike
Rail workers at South Western Railway and Eurostar have begun a 24 hour strike over separate disputes.
RMT union members at Eurostar say they face "dangerous" overcrowding at London's St Pancras station, while the SWR strike is over the long-running dispute about the role of train guards.
SWR said half of its services - in south-west London and southern counties of England - will be cancelled.
Eurostar said a normal service will run as other workers will cover the shifts.
Following the start of the walkouts at 00:01 on Saturday morning, the RMT said workers were "standing rock solid".
The union said it was available for "genuine talks" in both disputes.
Both strikes are set to last until 23:59 BST.
Further SWR strikes are planned for the coming weeks, as part of a total of eight days of strike action in July and August. The first walkout was last Thursday and the next will be on Tuesday 31 July.
The RMT has said changing the role of guards and extending driver-only services would compromise staff and passenger safety.
The union has accused the company of putting "private profits before public safety".
SWR said it will provide longer trains on Saturday, but passengers were advised to check their journey before travelling.
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A company statement said it was "frustrating and disappointing" that the RMT strike was going ahead and apologised to passengers.
"This is despite proposals we have put forward which are similar to that of another train operator, Greater Anglia, which the RMT has recently agreed to.
"We are urging the RMT to return to talks and end this damaging disruption to passengers."
About 140 staff are involved in the Eurostar dispute, with the union saying the international terminal at St Pancras had been reduced to "chaos".
Staff were bearing the brunt of public anger over delays to services, it said.
RMT general secretary Mick Cash said: "The conditions at St Pancras have been simply appalling in recent weeks, with dangerous levels of overcrowding on the concourse as services plunge into meltdown on the cusp of the busiest part of the year.
"RMT will not tolerate a position where our members are left to pick up the pieces due to corporate failures."
The union said it was going to ballot train managers for industrial action over the same issue.
A Eurostar spokesman said: "If the strike action goes ahead, our plan is to run a normal service so that all passengers booked to travel with Eurostar will be able to do so."