Six people were killed around Britain in the last days in a weekend of violence.
Four people died in London, including a pregnant 26-year-old woman, a 27-year-old man was attacked and killed in Maldon, Essex, and a murder investigation was launched after the death of a 47-year-old in Llanelli, south Wales.
The four killings in London took the total number of homicides in the capital this year to 67.
The attacks unfolded on one of the hottest weekends of the year, with temperatures hitting 34C (93F) in west London.
Expectant mother Kelly-Mary Fauvrelle was stabbed to death in south London on Saturday
Six people were killed in violent attacks around the country over the weekend
The first murder investigation of the weekend was launched after grandfather Andre Yan Irwin was found fatally wounded on a street in Llanelli in the early hours of Saturday morning.
His family, who are being supported by specialist officers, later paid tribute to the 'brilliant' family man.
They said: 'We are devastated at the sudden and tragic loss of a brilliant father, son, grandfather and fiancé.
'Andre was a great role model for his grandchildren, and will be very sadly missed.'
Later on Saturday, paramedics rushed to an address in Thornton Heath but were unable to save the heavily pregnant mother Kelly-Mary Fauvrelle who had been stabbed at her home.
The baby was delivered at the scene and remains in a critical condition in hospital - but a devastated aunt revealed he is 'unlikely to survive'. The baby was named by relatives as Riley in online posts.
A 37-year-old man arrested on Saturday was released 'under investigation' after being questioned by detectives. A second man, aged 29, arrested later that day remains in custody.
An ultrasound image uploaded to the mother's Facebook page in February saying she had been expecting this summer
After Ms Fauvrelle (left) was named as the victim of an attack in London, police in south Wales named Andre Yan Irwin (right) as another of the six victims of this weekend's violence
Further violence flared in south London later when a man in his 50s died following a fight in Lambeth on Saturday afternoon.
Police were called to Coldharbour Lane following reports of a fight where they found the injured 54-year-old.
The London Ambulance Service took the man to hospital but he was pronounced dead just after 10pm.
Two men have been arrested on suspicion of murder and remain in custody. Police have appealed for anyone with mobile phone footage to get in touch.
That evening, in the market down of Maldon, Essex, a 27-year-old man was killed after a brutal attack outside an Iceland supermarket.
Another victim, 26, suffered a broken jaw in the assault which unfolded in the sleepy market town of Maldon, Essex, on Saturday night.
Local police say violence flared at around 9pm when three men attacked the two victims.
Three men have been arrested on suspicion of murder and they remain in custody for questioning.
Forensic officers were today pictured outside the property wearing blue suits and purple gloves, while officers also remained on the scene
The violence continued later on Saturday night, when a man believed to be in his late 20s been stabbed to death in east London.