A 14-year-old girl has been left with potentially life-changing injuries after a suspected acid attack outside a school in west London.

A boy aged 16 and a 27-year-old woman were also injured after the substance, believed to be acidic, was thrown at pupils and a staff member outside Westminster Academy on Monday afternoon.

Police on patrol were flagged down by school staff following the incident in Alfred Road, Westbourne Park, at shortly after 4.40pm.

Both teenagers remain in hospital, with the boy’s injuries described as not life-threatening or life-changing.

The woman has since been discharged.

Scotland Yard said two officers were also taken to hospital as a precaution after they reported feeling unwell.

A spokesperson for the Met said: “Tests of the substance are ongoing. At this stage officers believe it to be acidic.

“Urgent inquiries are under way to identify and arrest those responsible.”

Westminster Academy remains closed on Tuesday, with lessons taking place online, according to a statement on its website.

Adam Hug, leader of Westminster City Council, said: “This is a truly shocking attack on school pupils and a member of staff.

“The council has been in touch with Westminster Academy and we will provide educational psychologists and any other support to help children through what is a traumatic ordeal. Our thoughts are with all those who have been affected.

“Clearly this attack will be unsettling for the whole academy and the wider community, and we will be working with police to provide reassurance and whatever support we can. We would urge anyone with information about what has happened to contact the police.”

Any witnesses or anyone with information is asked to call police on 101, quoting reference CAD 4987/30 Sept, or call Crimestoppers anonymously on 0800 555 111.