On Saturday, the Daily Mail spoke to a gang member, named "Off", who spoke of the reasons as to why people are now choosing acid rather than weapons to attack their victims.
Currently, there is no penalty for being caught in possession of acid-based chemicals as opposed to a knife or a gun.
The acid - known as a "face melter" due to the appalling effects it has on skin - can also be bought from the high street and can be thrown from a distance.
"It is a win-win situation," Off told the newspaper.
When describing the incident yesterday, the shopkeeper told the Mail Online: "They were two Bengali boys who came into the shop. They had acid on their face and they were burning - their skin was peeling off.
"I just gave them water, they were shouting and I gave them water and they were washing their faces.
"They said: 'We have got acid on us, we have got acid on us.'
"They were pouring the water over themselves in the shop, and it had got into their clothes. One of them was pouring it down his trousers.
"I was really scared. They were crying and saying: 'Put the water on me'.
"I called the ambulance at 6.56pm but they took half an hour to get here. They were on the phone for more than 20 minutes. It really p***ed me off. They took a long time.
"The fire brigade and police were here really quickly - they are stationed just around the corner.
"The ambulance caller was asking a lot of questions about it but what do I do - deal with the call or the water?
"I've never seen anything like this before. It's really scary.
"I think the boys had been attacked elsewhere and then got in their car and drove here to get water. Their car was outside.
"Their face and their legs were all burnt. One of them was saying: 'Put the water in my jeans'."
Witnesses said a blue tarpaulin has been erected to shield the victims from the public.
Four fire engines, police and paramedics are at the scene, which was cordoned off.
Footage posted online by Chris Lennon shows a topless man pouring water on to his face as he is surrounded by five paramedics as a policeman watches on.
Another man is seen sitting on the pavement as he has his blood pressure taken by the medics.
A spokesperson for the Metropolitan Police said: "Police in Tower Hamlets are dealing with a suspected noxious substance attack on two males in Roman Road, E2.
"Officers were flagged down in the area at 7pm on Tuesday, 25 July by the two males who are believed to be aged in their late teens.
"London Ambulance Service attended the scene.
"Both have been taken to an east London hospital for treatment after an unknown liquid was thrown at them. Their injuries are not life threatening.
"No arrests have been made.
"Enquiries are ongoing.
"A crime scene remains in place. Anyone with information concerning this incident is asked to call police on 101."
Earlier this month, Jabed Hussain, an UberEats driver, a Deliveroo driver, and four other moped drivers were left injured after they had a corrosive liquid sprayed directly into their faces as they waited at traffic lights in East and North London during a 72-minute rampage this month.
A 16-year-old boy has been accused of 13 separate offences in connection with the alleged spree. He denies the charges.
Another high-profile incident saw 20 people injured by acid spray in a London nightclub in March.
Arthur Collins, ex-boyfriend of TOWIE star Ferne McCann, was charged with that attack.
It was announced yesterday that police are now being provided with acid response kits to tackle the escalating scourge of violence.
West Midlands Police said that they are issuing guidelines for dealing with corrosive liquids in accordance with national police policy and 1,000 acid relief kits were given to Met Office police officers.
Five litre bottles of water are now to be stocked in emergency patrol cars across the capital to provide vital and immediate treatment on the scene.
