Hampshire Police are investigating after two women standing outside a mosque had water thrown at them in an apparent fake acid attack.
The women, dressed in traditional Muslim clothing, were targeted by the occupants of a black car which slowed down so a passenger could hurl the liquid at them.
CCTV captured the incident and showed the car speeding away from the Bashir Ahmed Masjid in Southampton.
The pair can be seen rushing away from the road, wiping themselves down, while one appears to be visibly upset.
The matter was reported to police who said the women were "understandably shaken".
Meanwhile the mosque has been forced to issue a safety warning to worshippers following fears that a subsequent attack could involve acid.
It follows a string of acid attacks, including five committed inside 90 minutes in London last week.
A message released by the mosque on behalf of one of the women read: "Sisters just to warn you to be careful when u are out and about, you all know about the recent acid attacks in London.
"Today my friend and I were standing outside Bashir Masjid in Portswood, waiting to be picked up when a group of men in a black car drove past us and threw water at us.
"We are both OK because it was only water, but if they get away with doing stuff like this then it could embolden them to next time use bleach or acid."
Footage suggests the assault took place at about 2pm on Tuesday.
Police confirmed they were treating the incident as a racially aggravated assault.
A Hampshire Constabulary spokeswoman said: "Our investigations are continuing today and we are in contact with the victims who were understandably shaken by this incident.
"The vehicle is described as a black estate car."
Anyone with information should contact police on 101