Rail services into the country's busiest station were disrupted for a second day ahead of a strike by guards which will lead to hundreds of trains being cancelled.
South Western Railway (SWR) services to and from London Waterloo were hit by a series of problems, including a broken down train at Woking, passenger alarms being activated on-board trains at Clapham Junction, and a passenger requiring medical assistance on a train at Wimbledon.
There was also a knock-on effect following a partial derailment of a train at Wimbledon on Monday.
Queuing systems were put in place at Wimbledon, and there was no London Underground District Line from the station.
SWR is one of five railway operators facing a strike on Wednesday by members of the Rail, Maritime and Transport union in disputes over the role of guards.
SWR said it expects to run around 60% of its services during the industrial action.