Emergency services were called to the incident, near the Scotmid shop at the junction with South Fort Street, just before 6:05pm.
Eye-witnesses reported seeing about six police cars, three police vans and an ambulance at the scene.
A worker at the Scotmid shop, who did not want to be named, said they witnessed a man come into the shop asking for bandages because someone “had been stabbed” outside.
The shop worker said: “They said that someone had been stabbed in the back.
“We gave them the bandages straight away. It was quite busy in the shop at the time.
“It looks like it happened on the other side of the road, directly opposite us and along a bit.
“Sometimes you get folk fighting in the pub round the corner but in terms of someone being stabbed, that doesn’t happen.”
The official Lothian Buses twitter account has also alerted passengers to a service diversion because of the road closure.
The tweet says: “Due to a road closure, services are not serving Ferry Road and are instead diverted via North Junction, Lindsay Road and Craighall Road in both directions till further notice.”
A police spokeswoman said: “We are currently dealing with an ongoing incident.”
It is understood officers are carrying out door-to-door inquiries in the area.
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