A 15-year-old boy arrested in connection with a noxious substance attack in which six people were injured has been released on bail.
Police were called to the area around the Stratford Centre in east London shortly before 8pm on Saturday to reports of an altercation between two groups of males during which the substance was sprayed.
They then ran from the scene, opposite the Westfield shopping centre, some into Stratford station.
Six males were hurt in the attack, with their injuries being described as not life-threatening or life- changing.
Officers arrested a 15-year-old boy in Stratford on suspicion of grievous bodily harm and he was taken to an east London police station for questioning.The teenager has been bailed to a date in late October.
Metropolitan Police Chief Superintendent Ade Adelekan, borough commander for Newham, said: "I would like to be very clear concerning this incident. What initially may have been perceived as a number of random attacks has, on closer inspection, been found to be one incident involving two groups of males.
"I recognise the lasting impact on victims of corrosive substance attacks. Our response to such attacks is continually improving through training and joint working with partners and we are working with the Home Office to explore possible restrictions around the sale of corrosive substances in conjunction with retailers and manufacturers."