A 37-year-old man has been given a life sentence after he stabbed his estranged wife to death in a car park after she began a relationship with a work colleague.

Niwunhellage Dona Nirodha Kalapni Niwunhella, known as Nirodha, 32, died at the scene at South Morgan Place in Riverside, Cardiff, on 21 August 2025.

Thisara Weragalage, from Pentwyn, who had been separated from her for months, previously denied murder, but at a hearing at Newport Crown Court in January he pleaded guilty.

Sentencing Weragalage at Cardiff Crown Court, Judge Daniel Williams said his “brutal selfishness” had cut Nirodha’s life short.

The court heard the couple had been separated for months, but on the morning of the attack Weragalage went to the residential car park knowing Nirodha would be there.

She was attacked with a 15cm kitchen knife, suffering catastrophic injuries to her face, neck, chest, arm and leg and died at the scene, left between two parked cars.

The attack was so ferocious that the handle broke off the knife used in the attack.

Witnesses, including a man walking his dog, saw Weragalage leaving the scene at speed in his Ford Fiesta, and they raised the alarm when they then found Nirodha lying motionless with horrific injuries nearby.

A short time later, Weragalage was spotted by a lorry driver on a pavement in the Tremorfa area of Cardiff in an agitated state and he threw himself in front of the rear wheels of the vehicle.

However, his injuries were not serious and after police and paramedics were called he was later arrested for murder.

He was detained under the Mental Health Act, but police found bloodied builder’s gloves in the passenger footwell of his car, along with the opened pack of knives.

After being arrested on suspicion of murder, he told detectives that his wife had “escaped” him and that she was “living with another”.

He claimed the knives were bought to “scare” her and that he could not remember how her injuries had happened.

After being charged with her murder, Weragalage later made an early guilty plea.

The court was told that the couple married in Sri Lanka in 2017 after meeting through a mutual friend.

The pair, who both had business qualifications, got married and considered moving abroad to further their education and improve their career prospects.

They eventually moved to Cardiff in 2022 where Weragalge said he had contacts. But the job in business in the UK did not materialise for Nirodha and she took a job in a care home instead.

By this time the marriage had run into difficulties. Nirodha disclosed to work colleague James Stephenson that her husband hit her and that they were also having sexual problems.

The court heard she became increasingly close to Stephenson. When Weragalage learned of this closeness, he became “obsessed” and began to spy on the pair at the care home where they worked.

When confronted with the suggestion that he was violent to his wife, he said her behaviour had caused him “to raise his hand”.

This behaviour caused Stephenson to fear for his and Nirodha’s safety and he broke off the relationship.

But by April 2025, Nirodha and Weragalage had moved out of their shared house and were living at separate addresses.

He said he could not live without her during this time, making 15 calls to her father in Sri Lanka as well as texting Stephenson saying he wanted to “reverse everything that has happened in the last two years”.

Stephenson had rekindled a relationship with Nirodha who texted her friend saying her estranged husband was threatening her.

“He’s going to kill James and he’s going to kill me,” she wrote.

Michael Jones KC, prosecuting, said that the murder was planned and premeditated and that sustained and excessive violence had been used.

“The prosecution case is that such was the ferocity of the attack on her that the knife broke during the assault,” he added.

Andrew Taylor, defending, said these were “tragic events” involving two “bright, ambitious and educated people”.

Taylor said he was “obsessed” with his wife and became “overtaken with jealousy” after discovering she was becoming increasingly affectionate with a colleague.

“He could not contemplate a life without her,” he added.

Judge Daniel Williams said Nirodha had “no chance” of surviving the attack.

He said she deserved a long and happy life that was cut short by Welagalage’s “brutal selfishness”.

Detective Inspector Graham Williams, of South Wales Police, said Nirodha was “much loved by her family and friends, and her life was ended by her jealous and cowardly former partner”.

“While no sentence can compensate for the loss of life. I hope the end of criminal proceedings helped bring them some peace,” he added.

Emma Davies, from the Crown Prosecution Service (CPS), said Weragalage “planned his attack, visiting the area several times leading up to it and buying the murder weapon”.

“His premeditation was a significant factor in this shocking killing,” she said.

Davies added that the CPS is working closely with police to build strong cases against those who commit violence against women and girls, ensuring “more victims of these abhorrent and devastating crimes receive the justice they deserve”.

“Our thoughts remain with the family and friends of Nirodha who have suffered a tragic loss,” she added.

In a tribute issued at the time of her death, Nirodha’s family described her as a “cherished daughter, family member and dear friend to many”.

“Nirodha will be forever remembered with peace, love and gratitude,” they said.

“She touched many lives with her kindness and warmth and her memory will continue to inspire us. Though her life ended too soon, the love she shared will always remain with us.” (BBC)