Police officers called to the scene on Westgate Street, E8, administered the woman CPR.
They were contacted at 8.52pm but a crime scene is still in place as officers investigate.
Footage of the scene showed several police units within the cordoned area, as well as at least one ambulance.
No arrests have been conducting at the time of writing.
Express.co.uk has approached Hackney Police for comment.
The victim who is believed to be in her 30s was reportedly found with a gunshot injury.
She was taken to an east London hospital and her next of kin were contacted.
The Met Police have launched an appeal for eye-witnesses or anyone with information that could help with the inquiry.
In a separate incident in South London, a man in his 20s was stabbed to death, according to reports.
The incident took place in Ramilles Close, SW2, in the Brixton Hill area of the capital.
Met Police were called to the scene at 5.59pm but the victim was pronounced dead at the scene.
So far there have ben no arrests made in connection to the stabbing.
A statement released by Met Police read: “Officers attended, along with colleagues from the London Air Ambulance, but the man in his twenties, was pronounced dead at the scene.
“Police are trying to trace his next of kin.
“No arrests have been made at this stage.
“A crime scene remains in place at the location, and officers are continuing their enquires.”