Armed officers responded to the triple shooting in residential Henley Road, Ilford around 12.16am.
Paramedics called police after reports of a fight in progress and shots fired.
At the scene officers found three men, two in their 20s and one in his 30s, with gunshot injuries.
One of the victims was pronounced dead at the scene. Another man died a short time later.
Scotland Yard believe they know the identity of one of the deceased and are working to inform next of kin.
A police spokesman said: “The third victim aged in his 30s was taken to hospital, where he remains in a critical condition.
“At this early stage there have been no arrests. Enquiries into the circumstances are ongoing.
“Crime scenes and road closures are in place.”
The double murder is the fifth killing within a ten-mile radius of east London in six days.
London Ambulance Service said: “We were called at 12.12am today to reports of a shooting on Henley Road, Ilford.
“We sent a number of resources to the scene, including two ambulance crews, an advanced paramedic, a medic in a fast response car, two incident response officers, a clinical team leader and members of our tactical response unit.
“We also dispatched a trauma team from London’s Air Ambulance which consisted of a paramedic and a doctor in a car.
“We treated three people at the scene and took one person to a major trauma centre. Sadly, despite the best efforts of our crews, two people were pronounced dead at the scene.”