Police launched a critical incident investigation when a woman, 18, died after being hit by a train at Hurstville on Thursday.
St George police were told of a woman, 18, in the rail corridor at Hurstville railway station about 1.50pm.
They searched the area and later received reports that the woman had been hit by a train and died at the scene.
An incident team from Central Metropolitan Region police will investigate, overseen by the Professional Standards Command.
A report will be given to the State Coroner.
Afternoon commuters encountered lengthy delays on the T4 Eastern Suburbs & Illawarra Line and South Coast Line, which is partially closed at Hurstville.
Services were running close to timetables by about 7pm.
EARLIER STORY:
A train hit and injured a person at Hurstville today, causing delays on the Eastern Suburbs and Illawarra line.
Emergency services arrived at the scene at 2.15pm.
Anyone concerned by the incident is advised to contact Lifeline 13 11 14.