A new kind of criminal attack is on the rise in London

Five different men in the London area were assaulted on Thursday night in a series of acid attacks around the area, with one victim suffering permanent facial injuries.

The five different attacks, which police say are connected, occurred over a 70-minute time span between 10:25 and 11:37 p.m. when the attackers rode up to the victims one by one and doused them in the face with the toxic substance.

Authorities reported the attacks were carried out by two male suspects riding on a moped, and during the fifth and final assault of the night, the suspects' moped was stolen and the attackers fled the scene.

Police have arrested one 16-year-old boy on suspicion of grievous bodily harm and robbery, and he is currently in custody at an east London police station, according to CNN. Law enforcement officials are hoping for more witnesses come forth in order to aid their investigation.

Acid attacks have been on the rise in London the last several years, according to a Metropolitan Police Service report. There were 166 recorded incidents in 2014, rising to 261 in 2015, and sharply increasing to 454 in 2016.

Police reported to CNN that the trend has continued upward this year. So far this year, not including Thursday night, the Met has recorded 119 such attacks.

British Prime Minister Theresa May's spokesperson called for new legislation to be passed in response to the rise in acid attacks.

“It is already an offense to carry acid or a corrosive substance with intent to cause harm," the spokesperson said. "And anyone using it can be prosecuted for pretty serious offenses including ABH and GBH. We are working with the police to see what more we could do."