But CityRail said there were delays of up to 50 minutes to services on the Illawarra and South Coast lines.

Passengers are advised to listen to station announcements and check indicators before boarding.

Passengers turned to twitter to vent their frustration about the delay.

A man on his way to Wollongong wrote that passengers were presented with few alternatives but to wait.

‘‘We have been asked to stay at this platform for an unspecified amount of time... If you have alternate transport, you should leave the train." are you freaking serious???’’ he said.

Passengers travelling between Central and Bondi Junction are able to use their tickets to catch Sydney Buses services instead.

An Ambulance Service of NSW spokesman said earlier it was a minor incident at Penshurst about 4.45pm with a south-bound train which had left Hurstville and was heading towards Cronulla.

''The first couple of wheels were off the line,’’ he said.

‘‘No carriages tipped over.

‘‘They’re just taking passengers off now.’’

Buses were called in to get rail travellers to their destinations as soon as possible.

Police asked drivers to take other trains past the affected site which resulted in delays.

See the CityRail Service Interruptions site or phone 131 500 for more updates.

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