The Independent Police Complaints Commission (IPCC) is appealing for anyone who saw or heard any part of the incident in South Shields.
The IPCC is investigating an incident in which a man was shot and seriously injured by Northumbria Police officers.
The incident took place in Frenchmans Way in South Shields at around 1.30am this morning (Tuesday, March 29).
It is understood Northumbria Police were responding to a report of an armed man in the street.
A 24-year-old man sustained an injury to his chest and is in a critical but stable condition in the Royal Victoria Infirmary in Newcastle.
A non-police weapon has been recovered from the scene.
Following notification of the incident by Northumbria Police, IPCC investigators travelled to the North East to supervise post incident procedures for the police officers involved as well as taking control of the scene of the shooting.
IPCC Investigators have been conducting house to house enquiries during the day and overseeing forensic scene examinations. Cordons will remain in place at the scene while this work continues.
The IPCC is asking anyone to come forward with information to assist the enquiries.
IPCC Commissioner Carl Gumsley said: “It is important that any incident in which a police firearm discharge results in serious injury or death is independently investigated.
“Our investigation will thoroughly examine all the circumstances surrounding this incident.”
The IPCC can be contacted via telephone on 0800 015 4877 or email firstname.lastname@example.org.