British police have arrested two teenagers after five acid attacks in less than 90 minutes across east London left several people with facial burns, including one with horrific injuries.
Two assailants on a moped pulled up alongside a 32-year-old man in the Hackney area of east London at on Thursday night and threw acid in his face before one of the pair made off with the victim's moped.
In the next hour and a half, three other men across Hackney and one in the neighbouring borough of Islington had corrosive substances hurled at them, police said.
After one of the robberies in Hackney, a man was left with facial injuries described by police as life-changing.
Police said they had arrested a 15-year-old boy in Stoke Newington, northeast London, and a 16-year-old male at a separate address in north London on suspicion of grievous bodily harm.
Metropolitan Police Commissioner Cressida Dick said the number of acid attacks appeared to have risen in the capital, though they remained relatively rare.
"I don't want people to think that this is happening all over London all of the time - it's really not, but we are concerned because the numbers appear to be going up," Ms Dick said.
"Acid attacks are completely barbaric," she said. "The acid can cause horrendous injuries. The ones last night involved a series of robberies we believe are linked."
The government said it was working with the police to see what more could be done to stop the use of acid for attacks.
"It's already an offence to carry acid or a corrosive substance to cause harm," Prime Minister Theresa May's spokeswoman said.
"We are working with the police to see what more we could do."