What happened
On 6 August 2021 Themba Nkomo, 61, a social worker with Haringey Council, went to a flat in Wood Green, north London, to carry out welfare checks on three children. He had asked for police support because residents had refused access. Officers cut a chain across the door with bolt cutters and went into the communal area.
A man was hiding round the corner. He ran at the social worker and stabbed him in the chest with two pocket knives, and carried on after he fell. The officers heard the shouting and ran to help, and one of them, who was wearing a stab vest, tackled the attacker. Nkomo suffered eight stab wounds, three of them penetrating his torso. The prosecutor told the Old Bailey that he survived through luck and the officer’s actions.
The outcome
The attacker, the children’s father, was convicted at the Old Bailey of one count of attempted murder and two of attempting to cause grievous bodily harm with intent. In March 2023 he was sentenced to a hospital order under section 37 of the Mental Health Act 1983, with a section 41 restriction order on grounds of risk to the public.
Haringey Council reviewed its risk assessment procedures and its lone working policy, brought in a psychotherapist for staff, and set up the Thinking Space programme with the Tavistock and Portman NHS Foundation Trust.
What went wrong
The visit had been risk assessed, and the assessment had asked for police. That is the strongest control in this case, and the attack happened anyway, in the gap between the outer door and the inside of the flat.
The attacker chose the moment. He was out of sight round a corner, in a communal area the team had to pass through, and he struck the person with no armour. The officers were seconds away and it was not enough. The prosecutor’s word for Nkomo’s survival was luck.
The door is the other finding. It carried a chain, it took bolt cutters to open, and the step through it led into a space nobody had cleared, with the attacker already inside it.
What it teaches
Risk assessment got the police to the door. It could not cover the corridor. What covers a corridor is positioning: who holds the door frame, who watches the corner behind the team, and where the unarmoured person stands while the chain comes off. Those are decisions made on the landing, and they can be written into a forced-entry procedure.
The second lesson is what a police escort means. It is not a guarantee. It changes who can respond, and it leaves the unarmed professional nearest the door.
Our lone working training covers joint visits and forced entry for staff who work alongside the police.
Questions for the room
- On a forced entry, who controls the door frame, and who is watching the corridor behind the team?
- Where does the unarmed professional stand when the chain comes off the door?
- What in your kit offers any protection against a blade, and have you tested it under stress?
- Your employer says it has reviewed its lone working policy. What changed for the next visit like this?
Evidence and limits
Confidence: confirmed. BBC News, the Guardian and Community Care were read in full for the record, and they agree on the date, the wounds, the conviction and the sentence. No source publishes the council’s risk assessment, so this page does not say what it required beyond police support, and the argument about positioning is ours. The offender is not named: the sentence was a hospital order and the name adds nothing to the lesson. The three children are not identified.
Sources
Reviewed 20 October 2026.