Witness heard screams for help before man found 'bleeding profusely' following NSW stabbing

A witness says they heard a man screaming for help before he was stabbed at a unit block on the NSW Central Coast.

Police officers found a 38-year-old man with serious stab wounds in the car park of a unit block on Gertrude Street in North Gosford about 6am.

He suffered stab wounds to his back, upper torso and a severe laceration to his wrist.

READ MORE: E-scooters to be allowed on pavements under NSW government plan

"I woke up to my neighbour downstairs screaming 'help, help'," resident Cassidy Orchard told 9News.

"He was just sitting at the bottom of the lift, his arm was bleeding.

"There was a lot of blood."

Brisbane Water Police Chief Inspector Colin Lott said an altercation between three people who live in the apartment complex broke out in the car park.

"We believe that's where they came upon each other, where the altercation began," Lott said.

"Other neighbours around the area came out to see what was happening, they saw the two persons of interest leaving the scene and the male victim was bleeding profusely."

Police are still searching for the two people they believe were involved in the stabbing - a 19-year-old female and a 24-year-old male.

READ MORE: Sussan Ley defeats Angus Taylor to become first woman to lead Liberals

Lott described the scene officers arrived at as "graphic."

"The male was lying on the ground near the elevator of the unit block and there was a large amount of blood," Lott said.

"There was also a blood trail of where he had run from as well."

Lott said police believe the three people involved were known to each other, with all three living in the housing commission unit complex.

The 38-year-old man was taken to Gosford Hospital in a critical condition.

DOWNLOAD THE 9NEWS APP: Stay across all the latest in breaking news, sport, politics and the weather via our news app and get notifications sent straight to your smartphone. Available on the Apple App Store and Google Play.