Distraught relatives rushed to help two teenage boys after they were stabbed, one fatally, in a street in Melbourne's west on Saturday afternoon, neighbours say.

A 17-year-old boy died after he was stabbed multiple times in the suburb of Kings Park about 2.30pm.

Forensic police at the scene of the stabbing in Kings Park on Saturday in which one boy was killed. Credit:Luis Ascui

Homicide Squad detectives are investigating the incident, which also left an 18-year-old boy in stable condition.

Both boys are yet to be identified.