The 23-year-old victim managed to travel more than four miles to Barnet Hospital, police said.
However, within an hour of arriving at hospital on Tuesday evening, he died from his injuries.
Detectives from the Homicide and Major Crime Command are investigating. Detective Chief Inspector Lee Watling, who is leading the investigation for the Homicide and Major Crime Command, said:
“We now believe Seun was stabbed in Cowper Gardens in Southgate and at that time there would have been a number of people there that had attended in cars.
“We are keen to speak to everyone who was there, and would appeal for them to contact us. We would also appeal to anyone who saw what cars were in Cowper Gardens at the time of the incident to also contact us.
“We continue to appeal for any witnesses to the attack, or anyone with any information about it, to contact us.