I was beaten up stopping a robbery – but it’s the online comments that really hurt

“Have you been in a fight?” asks a receptionist from behind a protective glass screen in A&E.

It certainly looks that way. It’s past midnight, there’s blood running down every side of my head, and one eye is swelling into a deep purple mess. I’m escorted by two policemen.

“We’ll leave you to it, if that’s okay?” says one of the officers.

In fact, I am the victim of a crime, having helped to separate a young woman from attackers and, in giving chase to the perpetrators, being rewarded with a hearty kicking.

By the time I get a taxi home from hospital, having undergone a facial X-ray and a CT scan, it is 5am.

Despite the efforts of online alt-Right commentators to portray London as a collection of lawless favelas, the growing neighbourhood where I live has been largely free of violent crime. Recent topics of concern in my street include litter and speed humps.

For more than a decade, I have walked home across our lovely park, which is well-lit and looked after with help from volunteers including the many local Bengalis who play cricket on it.

On Friday, some time after England has lost to the Netherlands in the Nations League, I am strolling along the usual path when a prolonged female scream pierces the night air behind me.

I run back to find a small crowd and a lot of shouting.

In the melee is a young woman being attacked, caught up with her assailants in a tangle of bikes and flailing limbs. Some onlookers have already intervened to pin the attackers to the path, but in the confusion the victim is still pleading for someone to call the police, and it is clear that everybody assumes that somebody else has actually done this.

I kneel on one of the suspects and call for help but the operator apologises and says “there’s a bit of a queue” for police as they’re very busy. I’m on hold for 999.

A lady with a small child, who has stepped in to help, kindly takes the phone from my shoulder to complete the call while I wrestle with the wriggling youth.

One of the suspects breaks free, helping the other to escape, and I give chase through the park until we’re all out of sight. At the edge of the park, we thread between passing cars whose drivers toot their horns angrily at the interruption. None stops to help or call the police.

Adrenalin jogs my memory and prompts three quick thoughts. First, a forgotten training course and the need for a "dynamic risk assessment" (how deep is this mess, and where’s the escape?). Second, a recent nearby fatal stabbing; these two could be armed with knives. Third, that even in an unarmed fight, I couldn’t beat an egg.

As I pause, they return to punch me until I’m on the ground, where each kick to the head is accompanied by a flash behind my eyes. Passers-by walk along the busy pavement, unconcerned.

In what’s left of my peripheral vision, an accomplice in dark blue joggers appears with a plastic cup of liquid. Mindful of recent acid attacks, I cover my face as much as possible and await the burning fluid. When it lands on my hands and arms, the dread evaporates: it is urine.

As I begin to wonder how much more kicking my head can stand, a shimmer of blue lights indicates the arrival of police. The suspects flee across a bridge. “Would you recognise them if you saw them again?” asks the first officer. Yes, probably.

The victim has got her phone back and is fine, but shaken. A man returns my phone. As the police take statements, a crowd of youths gathers round to taunt the officers and the victim, and me. One of them is wearing dark blue joggers and is carrying an empty plastic cup.

A picture of my bloodied head gets some attention on Twitter. As is often the case in 2019, reaction is polarised into two extreme and equally silly positions. I’m called "brave", which is preposterous. When did it become heroic to do the absolute minimum expected of anyone with human decency?

And, on the other hand, anonymous racist accounts say crime is caused by immigration – the word “diversity” is spat out as an insult – and Londoners have only themselves to blame for living in a city run by bogeyman Sadiq Khan. (This will be news to victims of the Kray twins or any other East End criminal down the ages.)

The bruises are healing – but the weaponised online discourse leaves a deeper scar.