Police have closed part of Bloomsbury Square with the junction of Bloomsbury Place in Central London following what is understood to be an attack involving acid.
Police paramedics and firefighters from the LFB were all scrambled to the incident on Tuesday at around 11.40am.
Anti Terror Police were also seen at the incident that remains an active investigation.
A large cordon has been put in place outside number 27 that is listed as a hotel and services flats.
Paramedics treated a white male in the back of the ambulance it is unclear if the man has been taken to hospital or his condition.
Police say they are currently dealing with an incident and a crime scene has been put in place
A spokesman for the Met Police said:
Police were called at 11:18am on Tuesday, 13 April to reports of a corrosive substance attack at Bloomsbury Place, WCI.
Officers, London Ambulance Service and London Fire Brigade attended.
At the scene a male, aged 30s, had been sprayed in the face with a substance that had inflamed/irritated his eyes.
At this early stage detectives believe that the attack was sustained during a personal robbery.
The victim was treated by medics and London Fire Brigade at the scene. We await further updates.
There have been no arrests.
A crime scene remains in place.
Anyone who witnessed this incident or captured moving footage is asked to contact police on 101 or Tweet @MetCC quoting 2507/13APR.