Sydney commuters are facing chaos on Australia’s busiest suburban rail network due to a power line falling on a train, which left hundreds of passengers stranded on board.

While passengers had begun leaving the train before 5.30pm, the issue continued to cause major delays across the Sydney Trains network during the Tuesday afternoon peak hour.

A train’s pantograph collided with overhead wires, bringing down a 1500-volt direct current cable onto the roof of a train near Homebush and shorting out the power, NSW Transport co-ordinator general Howard Collins told reporters.

NSW Transport advised of major disruption because of power supply issues near Strathfield.

The station in Sydney’s inner west is a major interchange for multiple routes and the incident is causing cascading delays elsewhere on the network.

Commuters were advised to delay “non-essential travel or consider alternative transport arrangements”.

It would take some time to figure out the exact cause but the focus was on safely isolating power and getting people home, Collins said.

“It’s difficult to ascertain how long this will take to fully rectify,” he said.

“You can’t sugarcoat it, this is an incident which is causing a lot of disruption to people and I apologise for that happening.”

Staff on board stranded trains were making sure people are safe.

“It’s better being on a train and probably [in] a bit of discomfort, than being exposed to the risk of power and or walking on the track, and that is more important,” Collins said.

“If you get very near or touch wires ... it will kill you straight away.”

Significant delays are expected across most of the network.

Buses are running and an agreement has been reached with rideshare operator Uber to avoid surge charging during the incident.

Services on the driverless Sydney Metro are unaffected, Collins said.

AAP with Paul Karp