Sydney trains restored after equipment vandalised by 'idiot'

A stretch of Sydney's train network was closed earlier this afternoon after signal wires were vandalised at Guildford.

Trains have since started running again between Cabramatta and Granville in both directions.

Transport for NSW said that signal faults were detected at 3am this morning.

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"Incident response teams were dispatched and found that critical cables had been cut by vandals," Transport for NSW said.

An image of the wires obtained by 9News showed them severed.

Repairs were completed about 1.30pm after signal engineers were dispatched to test the integrity of the system.

Trains still ran via Regents Park so passengers could change at Lidcombe or Cabramatta to complete their journeys.

"Sydney knows through bitter experience how badly a single track failure can affect services across the network," Minister for Transport John Graham said.

"Sydney's train system is complex enough without adding a failure due to one idiot vandalising a signal wire.

"Sydney Trains is working as fast as possible to rectify this incident."

Extra buses will remain on the affected stretch of the rail line.

The vandalism is not expected to significantly impact the afternoon peak.

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