Acid was squirted into a van and two people were attacked with a hammer after their car was stopped during a robbery in London.
This latest incident comes after Metropolitan Police statistics show there has been a sharp rise in acid attacks in the capital, with 1,800 being reported since 2010.
Officers were called to Pagnell Street, in Deptford, on Wednesday shortly after 2pm after the gang pulled in front of their victims, forcing them to stop.
Three people were in the targeted car when a number of suspects squirted a “noxious liquid” into the vehicle.
Police said a bag was stolen from one of the victims and two were assaulted with a hammer, before the assailants made off in the suspect car.
Two men aged 60 and 56 and a 47-year-old woman were taken to hospital for treatment to minor injuries, police said.
Khalid Salama, a resident living in Pagnell Street told the Evening Standard: “I heard a woman screaming. I wanted to go outside and see what was happening – the police were all over the place and doing their investigation.
“I personally feel safe here. We’ve been here about three years and we haven’t faced any risks but it’s not the perfect area and we’re probably going to move.”
Figures released in March revealed there has been a sharp rise in the number of acid attacks in London in the past four years.
In 2016 the dangerous substance was used in 454 crimes, compared to 261 the previous year, according to figures released by the Metropolitan Police to the BBC.
There have been no arrests made and detectives from Lewisham CID are investigating.
Any witnesses, or anyone with any information, is asked to contact police at Lewisham via 101, or by tweeting @MetCC.
Alternatively, call Crimestoppers anonymously on 0800 555 111 or visit crimestoppers-uk.org