Major disruptions are expected in the CBD on Friday evening, as details of a major incident in Bourke Street emerge.

A car was seen burning on the northern strip of Bourke Street near the Target store, and a man was shot by police after an alleged stabbing, according to the Age.

A Victoria Police spokesperson told Broadsheet a man was arrested at the scene and taken to hospital under guard in a critical condition.

The spokesperson advised a "small number of people" have been stabbed and police are not seeking anyone further at this time.

A witness at the scene told Broadsheet: "I just drove out of the city, cops were racing down Elizabeth Street."

Bourke Street is currently blocked between Swanston and Russell streets, and people are being advised to avoid the area.

At the time of publishing, Swanston Street trams are delayed in both directions, and route 86 and 96 trams are diverting along La Trobe Street between Melbourne Museum and Spencer Street, according to Yarra Trams.

Metro Trains tweeted CBD railway stations remain open and train services are running normally. For updates, head here.

Anyone with information is being asked to make a statement at the West Melbourne Police Station.

The Guardian is providing live updates here. For further updates follow Victoria Police.