Police are hunting two men following five suspected acid attacks in less than 90 minutes in east London.
One victim was said to have suffered “life-changing” injuries during one of the attacks late on Thursday, local time.
The Metropolitan Police say the incidents appear to be linked and two involved victims having their mopeds stolen.
The attackers pulled up to the five separate men and doused them in the corrosive liquid, police say.
At the start of the spree, a 32-year-old moped driver had been approached by the pair as he drove in Hackney.
The two male suspects had tossed the noxious substance into his face before one of them jumped on his vehicle and the other drove away on the vehicle on which they arrived.
About 40 minutes later, another victim was attacked in Shoreditch by two men on a moped, having liquid thrown in his face.
Within 15 minutes the attackers appear to have struck again, launching the corrosive substance at a man in Stoke Newington, causing “life-changing” injuries.
The next assault was reported to police at 11.37pm (8.27am on Friday AEST), with a man confronted as he sat on his moped in traffic in Clapton.
After again spraying the liquid in a victim’s face, the moped was stolen and both attackers fled.
Following the incidents in Hackney, officers were made aware of a similar attack reported in Islington. At 10.49pm, a man was reported to have had a corrosive substance thrown in his face by two males on a moped.
All five victims were taken to hospital and police believe all five incidents are linked.
Met Police said a teenage male has been arrested on suspicion of grievous bodily harm and robbery. He is currently in custody at an east London police station.
Spate of acid attacks in London
There has been a spate of acid attacks across London this year.
Two Australian sisters, Isobella and Prue Fraser, were injured in a separate acid attack at a London nightclub in April this year.
And aspiring model and business student Resham Khan and her cousin James Muhktar were sitting in her car on her 21st birthday on June 21 when when acid was thrown at both of them.
A man, 24, has been charged over the attack.