'Hysterical' woman phones police after stabbing

A HOMICIDE investigation has been launched after a man was fatally stabbed north of Brisbane.

Emergency services were called to Blyth Rd at Murrumba Downs about 5.45am to find a man lying in the middle of the road with "significant injuries".

He died at the scene and a crime scene has been declared.

Speaking from the scene, Inspector Steve Flori said the man was with a woman at the time of the stabbing.

She phoned police and was hysterical.

"That woman is uninjured however she is extremely distressed," he said.

"We are still trying to find out exactly what's happened but I can say that we believe another party was involved.

"We have launched a homicide investigation."

The man has yet to be formally identified and the relationship between he and the woman is unknown.

"There is some disparity between their ages so whether they are friends ... whether they were just together is still a mystery."

The man is believed to be about 40-years-old.

Police have taken the young woman back to a station in an attempt to calm her down.

Investigations are ongoing.