Some services were forced to skip stations as passages crowded platforms following an incident

Sydney’s commuters were caught out after an incident at a train station caused major disruptions to some services.

Sydney commuters have faced another peak hour of chaos, after a fatality at an inner-city train station.

Transport NSW said the T1, T2, T9, Blue Mountains and Central Coast and Newcastle lines were affected after “an incident requiring emergency services at Macdonaldtown.”

Trains towards the city were skipping stations from Croydon to Macdonaldtown after the incident.

“There are delays on all lines except the T4 Eastern Suburbs & Illawarra Line and the T7 Olympic Park Line,” Transport Management said at 4.30pm.

Most of Sydney's train lines were affected by the incident. Picture: Supplied

Passengers were advised to use local buses or catch citybound trains to Redfern and change for trains away from the city for stations on the innerwest line.

Trains later started stopping at Macdonaldtown, Summer Hill, Lewisham, Petersham, Stanmore and Newtownagain.

But passengers are still advised to allow plenty of extra travel time on Sydney Trains services.

The backlog caused chaotic scenes at major train stations, including Parramatta in Sydney’s west.

Police were called in to control access to the train hub, as hundreds entered the station.

Large crowds built up at Parramatta train station after an incident at an inner-city station. Pictur: Supplied / Facebook

However, delays continue on most train lines except the T4 Eastern Suburbs & Illawarra Line and the T7 Olympic Park Line.

Passengers should listen to announcements and check information displays as train stopping patterns may change.

Buses may also supplement some train services.

For the latest public transport information, visit www.transportnsw.info or download a transport app.