The Met Police is "seeing some links" between criminal gangs and the recent spike in acid attacks in London, a senior officer has said.
Deputy Commissioner Craig Mackey said the force was "seeing a move across" to gang members using acid and corrosive fluids in attacks.
But he cautioned evidence was limited as "it's a small data set".
On Monday, MPs debated measures, including tougher sentences, for attacks involving corrosive substances.
The government has also proposed classifying such substances as dangerous weapons.
The deputy commissioner supported efforts to tackle the issue, saying some of the substances are "not even defined by law".
"The impact this sort of attack has on people is extraordinary," he said.
"Many of us have been unfortunate to see quite a bit in our services but acid attacks are really extraordinary and strike at something quite horrific in people's psyche."
Mr Mackey told the London Assembly Police and Crime Committee there were 458 acid offences recorded in London last year, with 63% being assaults.
He said 23% were related to robberies and the rest were criminal damage, while the majority of victims were aged between 15 and 29 and nearly a third were Asian.
"About 80% of the victims and about 82% of the suspects are male so it's a predominantly male-pattern behaviour," Mr Mackey said.
"East London is a hotspot ... although there are offences across London."
Mr Mackey's comments come as four teenagers, two aged 17 and two 18, were arrested for possession of a suspected corrosive substance following a stop and search in Leytonstone, east London on Wednesday.
A bottle of suspected corrosive substance, gloves and a balaclava were recovered from the car the suspects were travelling in.
Last week, five separate male victims - all on mopeds and including a fast-food delivery driver - were allegedly targeted by two moped-riding attackers in north and east London.
"We are seeing some links - although it has to be treated with caution because it's a small data set - of a growing feature between named suspects in acid attacks who also feature in our gang matrix," Mr Mackey said.
"So please don't read that as gangs have all moved lock, stock and barrel into acid, but we are seeing a move across.
"We have hypotheses for this, we have tests that we think, 'is it something around a focus on knives and knife crime sentencing', but there is no evidence to support this yet. It's just something that we are looking at."