London violence: Peter Petrou's family 'devastated' after second murder

The killing of man found stabbed to death outside a McDonald's in London was the second murder his family has had to go through.
Peter Petrou's sister Tracy Meade was murdered nearly 30 years ago and there have been no convictions in the case.
Mr Petrou, 37, was one of seven people killed in as many days in the capital last week.
Detectives have yet to make any arrests after he died in Kilburn last Thursday.
One of Mr Petrou's other sisters, Emma, said that his family are "deeply devastated".
"We cannot begin to imagine how we are going to cope with this type of tragedy again especially if the perpetrator is not caught," Emma said.
"Peter was much loved by his large family and many friends. He was the life and soul of everything and the void he has left will be hard to fill."
Mr Petrou was attacked in Victoria Road, off Kilburn High Road and his body was found next to a McDonald's last Thursday.
Six hours after his killing, another man also aged in his 30s, was driven to hospital with stab injuries he sustained during a fight in Lytton Avenue, Enfield.
He died from his injuries in hospital and police in London launched their seventh murder investigation in as many days.
A week earlier, on Friday 10 July, Muhammed Samir Uddin, 19, was fatally stabbed outside Crossharbour DLR station in Poplar.
The following day Mixed Martial Arts champion Jahreau Shepherd was fatally stabbed at his 30th birthday party on the Black Prince Estate, Kennington.
In the early hours of Sunday 12 July Dean Edwards, 43, was shot in the back of the head as he returned from a pub in Penge.
Then last Tuesday Ahmed Yasin-Ali, 18, was stabbed to death in a car park by Maida Hill. The following day 27-year-old Billy McCullagh was shot dead in Harlesden.