Sydney trains resume following police operation

Trains are back up and running in Sydney after a police operation at Sydney's international and domestic airport train stations, which saw passengers evacuated from several platforms.

The train stations were locked down by officers at about 1pm this afternoon.

Train services were suspended between Central and Sydenham via Airport stations with a bus service operating as a replacement.

All of the train services are now back up and running, but passengers have been warned to expect delays and allow for extra travel time.