Two men have been left with facial injuries after they had a “corrosive substance” thrown at them during a street brawl.
Emergency services rushed to Argyle Square, near King’s Cross station, on Tuesday afternoon after the attack.
Police said those involved had all fled the scene, but the victims were found injured nearby.
Pictures from the scene showed ambulances, a fire engine and a police presence on nearby Crestfield Street.
A Metropolitan Police spokeswoman said: “Police were called at 13:33hrs on Tuesday, 12 February to reports of an altercation between two groups of males on Argyle Square, Bloomsbury.
“All parties had left the location before officers arrived at the scene.
“Two men were later found nearby with facial injuries reported to have been caused by a corrosive substance.
“They have been taken to a nearby hospital; we await an update on their condition.
“No arrests have been made. Enquiries continue.”
A worker from Kings Cross Inn Hotel said Crestfield Street was closed and there was a heavy police presence outside.
He said he believed there was a fight between two groups of teenage boys and “then someone had acid thrown on them”.
A London Ambulance Service spokesperson said: “We were called at 1:51pm today (12 February) to reports of an incident on Crestfield Street, Bloomsbury.
“We sent an ambulance crew and our hazardous area response team (HART) to the scene.
“We treated two people and took them both to hospital as a priority.”