A young driver has died in a single-vehicle crash in western NSW on Sunday.

The 23-year-old man was driving on the Mid-Western Hwy at Cowra when his car left the roadway about 2am.

He smashed into a tree and “was trapped for some time” inside his car, NSW Police said.

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Police officers were the first to arrive at the scene and gave the young driver first aid.

NSW Ambulance paramedics then arrived and treated the 23-year-old man, but he died.

Investigations into the crash are ongoing.

Anyone with information or relevant footage is urged to contact Crime Stoppers.