The Met has launched a parallel criminal investigation while a probe into policing standards takes place, after a suspected hand grenade and gun were found in the flat where a police officer shot a man.

The 28-year-old was wounded during a “domestic disturbance” in Knights Close, Homerton, just before 10pm on Tuesday night, and is still fighting for his life in hospital.

Specialist firearms officers had been drafted to the flat where someone was reportedly “armed with knives and making threats to kill”.

One police officer was stabbed during the incident, but his injury is not believed to be life-threatening, according to Scotland Yard.

Homes were evacuated as a precaution while specialist officers assessed the suspected hand grenade and suspected firearm discovered during a search of the property. The devices were deemed safe and removed.

The Met’s Directorate of Professional Standards is supporting the Independent Office for Police Conduct (formerly the Independent Police Complaints Commission) investigation.

Meanwhile the Central East Command Unit has launched its own investigation into the assault on the police officer and firearms matters.