LONDON (LBC RADIO/CNN) - Two teenage boys are under arrest over a series of acid attacks.
The five attacks happened within 70 minutes in the boroughs of Hackney and Islington on Thursday.
One of the victims' injury is described as life-altering.
Authorities say he was on a moped when two attackers on another bike pulled up and doused him with acid.
The attackers then split up, and one stole the victim's vehicle.
London's Metropolitan Police Chief Cressida Dick said she is concerned about the growing number of acid attacks in the city.
Speaking on LBC radio in London on Friday, Dick said attacks such as those that happened overnight Thursday are "completely barbaric" and until recently were "incredibly infrequent."
"The acid can cause horrendous injuries. The ones last night involved robberies we believe are linked - a series of robberies. I'm glad to say we have arrested somebody," she said.
"I don't want people to think this is happening all over London all the time. It's really not," Dick said. "But we are concerned because the numbers appear to be going up. We will arrest people. We will enforce the law as we can. We are working very closely with the Home Office to try to see whether there's any changes in the law required."
She says it's relatively easy to purchase harmful liquids, adding that it's something about which she's talking with UK government officials.
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