South West Trains said that all services had been brought to a halt by the incident.
The company say they were briefly stopped and were now normal.
Thousands of passengers would have been on trains on that section of line at the height of the rush hour.
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Holly has Wednesday's forecast for the west of the region.
Holly has Wednesday's forecast for the east of the region.
A huge fire at a hotel in Hampshire - also a popular wedding venue - has left couples in limbo about their big days.