A woman has died as two cars collided in NSW‘s mid north.

The crash occurred between a bronze Suzuki hatchback and a silver Alfa Romeo hatchback on Main Rd, Fennell Bay in Lake Macquarie about 1am on Monday.

After the collision the Suzuki crashed through a fence and hit a tree, police said.

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The Suzuki driver, a 38-year-old woman, died at the scene.

The Alfa Romeo driver, a 37-year-old man, underwent a roadside breath test which returned a negative result.

He was taken to John Hunter Hospital for mandatory testing.

“A crime scene has been established and officers attached to Lake Macquarie Police District commenced an investigation into the incident,” NSW Police said.

A report will be prepared for the coroner.