A teenager has been arrested after four men were attacked with an “unknown substance” near a shopping centre and railway station in Essex. which eyewitnesses described as an "acid attack".
The victims were taken to hospital to be treated for facial injuries, although they were not thought to be life changing or threatening.
Firefighters were filmed as they hosed people down as they sat on a low wall wrapped in foil thermal blankets.
Eyewitnesses, who shared video and photos of the incident on social media, described the incident as an "acid attack".
Detectives said a 17-year-old boy was arrested on suspicion of grievous bodily harm (GBH) following the incident.
He was also taken to hospital as a precaution.
Officers are also hunting for two other people believed to have been involved in the incident.
A spokesperson for Essex Police said: “We were called shortly before 8.10pm on 25 February with reports four men had been assaulted by a group of men on a footbridge linking Chafford Hundred train station and intu Lakeside shopping centre.
“They have been taken to hospital with facial injuries, which are not believed to be life changing or life threatening."
They added: “A 17-year-old boy was arrested on suspicion of causing grievous bodily harm. He has also been taken to hospital as a precaution. Inquiries are ongoing to find two other people believed to have been involved in the disturbance."
c2c Trains, which runs through the station, said its services were not affected by the incident.
Essex County Fire and Rescue Service was unavailable for comment.