A marriage torn apart by suspicion and obsession ends in a savage knife attack, a life sentence, and a grieving family searching for peace.
Murder of Nirodha Niwunhella in Britain: Husband sentenced to life imprisonment
A British court has sentenced her 37 year old husband, who was accused of stabbing his wife Nirodha Nyunhella to death in Britain, to life imprisonment.
The murder took place after she began an affair with a colleague at work.
The 32 year old woman, known as Nirodha, also known as Nirodha Nyunhella, was stabbed to death in a car park in South Morgan Place, Riverside, Cardiff on 21 August 2025.
Her husband, Thisara Weragalage, who lives in Pentwyn and had been estranged for months, had previously denied murder charges but pleaded guilty at a trial at Newport Crown Court in January.
Sentencing Weragalage at Cardiff Crown Court, Judge Daniel Williams said his brutal selfishness had shortened Nirodha’s life.
The court was told that the couple had been separated for months, but on the morning of the attack, Thisara had gone to her residential car park, knowing Nirodha was there.
She was attacked with a kitchen knife about 15 cm long and suffered serious injuries to her face, neck, chest, arm and leg. Nirodha was found dead between two cars parked in the car park.
After the murder, he left the scene in a distressed state and was hit by a lorry.
He was detained under the Mental Health Act, but police later found bloodstained gloves and an open pack of knives in his car.
After being arrested on suspicion of murder, he told detectives his wife had run away from him and was living with someone else. He said the knives were brought to scare her and claimed he did not remember how she was injured.
After being formally charged with her murder, Weragalage later pleaded guilty.
The couple had married in 2017 in Sri Lanka after meeting through a mutual friend, the court was told. They later moved abroad in search of further education and career opportunities, eventually settling in Cardiff in 2022. Weragalage said he had connections in the city, but a planned job in the UK business sector did not materialise, and Nirodha found work in a care home instead.
By then, their marriage was already under severe strain. Nirodha confided in her colleague James Stevenson that her husband had assaulted her and that they were facing sexual difficulties. Evidence presented in court revealed she grew increasingly close to Stevenson.
When Weragalage discovered their closeness, he became obsessed. Prosecutors described how he began monitoring the pair from the care home where they worked. Stevenson later said he feared for his safety and ended the relationship after witnessing Weragalage’s behaviour.
By April 2025, the couple had separated completely, moving into different addresses. Despite this, Weragalage continued contacting Nirodha. He made 15 calls to her father in Sri Lanka and sent messages to Stevenson saying he wanted to undo everything that had happened in the last two years.
Nirodha texted a friend that her husband was threatening her. “He’s going to kill James, he’s going to kill me,” she wrote, a chilling message that would later take on tragic significance.
Michael Jones KC, leading the prosecution, told the court that the fatal stabbing was pre planned and carried out with extreme violence. The severity of the attack was such that the knife broke during the assault.
Andrew Taylor, defending, described the case as a tragic incident involving two ambitious and educated individuals with promising futures. He said Weragalage had become consumed by jealousy and obsession after learning of his wife’s growing affection for a colleague. He could not imagine life without her, the court heard.
Judge Daniel Williams stated that Nirodha had no chance of surviving the sustained and frenzied attack. He said Weragalage’s brutal selfishness had robbed her of the long and happy life she should have had.
Detective Constable Graham Williams of South Wales Police described Nirodha as much loved by her family and friends. He said her jealous ex husband had ended her life and expressed hope that the life sentence would bring some measure of justice, even though no punishment could compensate for such a devastating loss.
Crown Prosecution Service representative Emma Davies said the murder was clearly premeditated. She confirmed that Weragalage had visited the area several times before and purchased the weapons used in the killing. His pre planning was a significant factor in what she described as a shocking murder case linked to domestic violence and violence against women.
Davies added that the CPS continues to work closely with police to build strong criminal cases against perpetrators of violence against women and girls, ensuring victims receive the justice they deserve.
In a statement released after the verdict, Nirodha’s family described her as a beloved daughter, family member and friend to many.
“Nirodha will forever be remembered with love,” they said.
“She touched many lives with her kindness and warmth, and her memory gives us courage. Although her life was short, the love she shared will always be with us.”
