While Ambulance Victoria said paramedics did not treat anybody at the scene in Melbourne's south-east, police said it was an attempted self-harm incident that resulted in minor injuries.

It was initially reported that a person was hit by a train at 6.05pm.

A Metro Trains spokeswoman said services on the Sandringham line between South Yarra and Elsternwick were restored at 7.50pm.

However, there are still major delays for the Belgrave and Lilydale lines.

Commuters face a 45 minute delay after signalling issues in the Box Hill area caused problems between Camberwell and Ringwood.

For help or information visit beyondblue.org.au, call Suicide Helpline Victoria on 1300 651 251, or Lifeline on 131 114.