Officers from British Transport Police were called to the scene at 8.47am to ‘reports that a car had been struck by a train’, a spokesman confirmed.
Paramedics also attended, but two people were sadly pronounced dead at the scene, the spokesman said.
Officers are now working to identify the bodies and inform the families, according to the spokesman.
The scene is being examined by officers.
Trains are unable to run between Horsham and Barnham due to the incident, a National Rail spokesman confirmed.
Disruption is likely to be in place for most of the day.
A rail replacement bus service will be implemented between Horsham and Barnham, however this will be an infrequent service, the spokesman said.
Services will be severely delayed towards Horsham, Barnham, Portsmouth Harbour and Southampton Central.
Customers should use alternative routes as services are severely delayed.