A woman has died after being shot by police in Melbourne’s north-east.

Victoria Police says officers were called to an address in Kett Street, Lower Plenty at about 6:30pm on Friday after reports a woman aged in her 20s was assaulting another woman aged in her 50s.

Police say that after they arrived at the scene, officers were “challenged” by a woman in her 20s, who was armed with a knife.

They said that woman was subsequently shot by police and died at the scene. 

A second woman was treated by emergency responders but also died at the scene.

Detectives are not looking for anyone else in relation to the incident and believe the two women knew each other.

The homicide squad is investigating.

The probe will be overseen by the Professional Standards Command, which the force says is protocol when a police firearm is discharged.

ABC/AAP