Computer lecturer ‘tried to kill wife outside their child’s school’

A university lecturer stabbed his estranged wife more than ten times outside their child’s parents evening, a court heard.

Dr Ying Zhang, 55, a lecturer in computer studies would have killed Hannan Xiao, 52, who teaches cybersecurity, had a passer-by not stopped the attack by kicking him in the head, jurors heard.

Ms Xiao sobbed ‘stop it, help me’ as she was stabbed with a kitchen knife in the chest, neck and back outside their child’s school in Barnet.

Zhang had repeatedly assaulted his wife and she had been to court several times to stop him harassing her, the Old Bailey heard.

The couple are both Chinese citizens. They met in 2004 and married in the UK in 2006 to live in Watford.

Ms Xiao is a senior lecturer in cyber security and director of online studies at King’s College London.

Zhang was senior lecturer in Computer Studies at the University of West London, having gained a postdoctoral qualification from the University of Cambridge.

They had separated by the time of the incident.

Prosecutor Walton Hornsby said: ‘The prosecution say that the defendant was in a state of cold fury with her for pursing with a divorce.

‘He was not happy that she had made this request and asked her if she really wanted the divorce.

‘She replied “Yes”. He said she “should think about it… you are too quick”.

‘He texted her asking for forgiveness saying that he still wants the family and the children.

‘This was a few days before the 21st. He said she should move out and leave him and the children in the family home. She said “That’s not acceptable.”

‘Although her husband had been notified of the meeting he was not invited or expected to attend, only one parent being allowed to do so.’

Ms Xiao did not know Zhang was in the meeting, and when she left he followed her to her car.

CCTV shows him leaving the meeting and returning with a rucksack, which the prosecution say contained the knife.

He followed her out of the meeting to her car and when she spotted him they had an argument.

He then chased her into the road and began to attack her with the knife, Mr Hornsby said.

He said: ‘When she left the school she returned to her car and found him behind her.

‘He asked to get into the car saying that his was broken. She refused and said she was scared of him. She said he could get a train.

‘She ran into the road. She remembers him running up to her and catching hold of her and then “he was just stabbing me”.

‘She asked him what he was doing and he didn’t say anything. She turned away from him exposing her back in order to protect her chest and heart.

‘The next thing she remembered was lying on the street on the road and an “old man” holding her chest and she was covered in blood, and then a lady came to give her help who said she worked in a hospital.

Eyewitness Richard O’Brien said Zhang seemed relentless and didn’t flinch at anything anyone said.

He said: ‘I thought that the female was going to lose her life if I did not stop him.’
He said Zhang was using as much force as he could when he was stabbing her.

Mr O’Brien kicked Zhang in the side of the head, knocking him unconscious and restrained him, the court heard.

Mr Hornsby said: ‘It was only the intervention of a member of the public that prevented the defendant from continuing the attack and killing her.

‘She did receive life threatening injuries, and it was only emergency surgery that saved her life.

‘She very nearly died, and it was Mr O’Brien’s action that saved her life.

‘Given the toxic history of the marriage and the severity of the stabbing, the prosecution case is that there is no doubt that the defendant intended to kill Hannan Xiao.’

Zhang had blood on his hands when he was taken away by police.

An expert said the injuries to Ms Xiao’s heart and lung were life threatening and she would have died without medical intervention.

Mr Hornsby said: ‘As far as the marriage was concerned it was not always a happy one and it was marred by a number of incidents of domestic violence.’

Zhang accepted a caution for assault in relation to a violent argument at their home in Hatfield in July 2005, the court heard.

Ms Xiao said her husband was hard to control when he loses his temper.

Zhang pressurised Ms Xiao to sign over her interest in the family home and threatened to kill her, in September and December 2006, jurors heard.

She reported further assaults in May 2008 and June 2012. In the first he threatened to kill her with a knife.

The couple separated after an incident of battery in August 2020.

Zhang accused his wife of being unfaithful with somebody at work and demanded to see her work emails. He assaulted her, allegedly saying ‘I’ll kill you one day’.

A non-molestation order was granted by Watford Family Court in October 2020 which prevented Zhang going within 100 metres of the family home.

Zhang breached the order numerous times, it was said.

Four days before the attack he booked a room in a guest house on the road where his wife lived and used it to watch her behaviour and take photographs of her, the court heard.

Zhang, of Stonecross Road, Hatfield, denies attempted murder and possession of a bladed article.

The trial continues.