CNN  — 

Acid attacks are a very particular type of cruelty. Assailants typically approach their victims and throw some cocktail of corrosive chemicals on them, burning their flesh, disfiguring their faces and bodies and causing excruciating pain. They are rarely fatal, but all it takes is a few seconds and a splash to derail a life.

Such vicious incidents have long been a problem in several south Asian countries. But in London, the trend has seen a steep and worrying rise.

According to data from the Metropolitan Police in London, 454 acid attacks were reported in 2016.

This is a huge increase ( >173%) from the 261 reported attacks in 2015, and almost triple the number of attacks reported in 2012.

For the six-year period from 2010 to 2016, the number totals 1,805. (Three resulted in deaths.)

The obvious question: Why

The obvious question is also one of the hardest to answer. Why is this happening at such a rate? There’s no firm explanation, but police say the attacks can be easy to carry out because the supplies are easy to buy and can be carried around in a virtually undetectable manner, like in a water bottle.

Simon Laurence, chief superintendent for the Hackney borough in London, told CNN there’s no onus on retailers to restrict or questions sales of such chemicals.

“It’s drain cleaner, oven cleaner, ammonia – different types of household products which can be bought,” he said. “My plea is to sellers to have moral responsibility, social responsibility, to ask the questions.”

In the first two months of 2017, London saw 49 attacks.

The police were only able to provide concrete numbers for January and February.

But it happened again on July 13, when five men were attacked with acid in London in one night alone. Police are treating them as linked assaults.