London: The Metropolitan police are seeing an emerging link between gang violence and acid attacks in London, according to the force’s lead for corrosive-based crime.

Detective Superintendent Mike West said that connections had been made between suspects and those known to be in organised crime.

“We have a ‘gangs matrix’ we use for intelligence-led policing. There are around 3,000 gang members on it. When we do a comparison with suspects we know, some are appearing on that matrix, so there is an emerging link between gangs and acid attacks,” he said. Referring to the mode of transport often used in attacks, West added: “With those using it [acid as a weapon] on mopeds, they may not be in a defined gang but that doesn’t stop them being part of an organised criminal network.”

Early on Monday four teenagers were arrestedin north London on suspicion of being involved in acid attacks.

While such attacks are still far less common than incidents of knife crime — there were some 32,000 knife offences in England and Wales in 2016 — the number of attacks involving corrosive fluids has risen sharply in recent years. Last year in London there were 454 acid-related crimes compared to 261 in 2015.

In a parliamentary debate over tougher sentences last month, the home secretary, Amber Rudd, said changing the current guidelines would make sure those who used noxious liquids as a weapon felt “the full force of the law”. West said the Met was also looking to change police powers, so it can crack down on those carrying corrosive substances if there is evidence of malicious intent.

“If you are simply carrying a corrosive substance in a bottle at the minute, you could be carrying it innocently,” he said. “There needs to be a clear differentiation between when carrying it is innocent and when it becomes a criminal offence.

“We want to change the burden of proof, so if you’re carrying it in a different bottle, for example a sports cap one — it’s more likely you can be charged. Obviously the evidence needs to be there as well. We are meeting with the Home Office next week to discuss regulation.” West said the victims and offenders tended to be in younger age bracket, from mid-teens to late 20s. He said Met officers would be going to schools to educate young people on the dangers.

“We are designing a programme delivered to schools. We want to get officers going into schools and talking about the impact of attacks on human beings but also the risk on their own lives,” he said.

“I am working in a smaller group with the Home Office to shape future legislation of certain products. There could be changes in the law with regards to police powers and how companies manufacture and retail certain substances and that needs to be balanced against consumer needs.”

Last week, the Royal College of Emergency Medicine said that with acid attacks increasingly common, the public needed to be taught how to help victims.

Doctors say bystanders at the scene of an incident should help remove contaminated clothing quickly and safely, and wash off the acid with lots of water, which can lessen scarring.