A man has been arrested after a woman and child, who police believe to be mother and son, died with stab wounds in north London on Tuesday.
The victims were pronounced dead at the scene.
An investigation has been launched, led by detectives from the Met’s specialist crime command, and a 37-year-old man has been arrested on suspicion of murder.
The deceased and the arrested man were known to each other, police said.
A local mother-of-two said the deaths had left her feeling scared.
Becky, 39, who did not give her last name, said of her neighbours: “Oh my God, it’s just shocking, it really is.
“Yes, I knew the family, nice, quiet Chinese family, from China. I’m bad with names.
“I’m a mother of two girls, similar age (to the child victim), they have never played but they have met them before.
“I have cried so much, earlier in particular when I heard that a child was involved, that was devastating.”
Mother-of-two Rummana Chowdhury, 37, said: “I don’t know them, it’s definitely very sad, it’s shameful.
“I can’t believe this, it’s unbelievable.
“It’s scary and sad as well because this morning everything was OK and suddenly this happened.”
Chief Superintendent Sara Leach, policing commander for the North West, including Barnet, said: “The whole community will be shocked and saddened to hear of this terrible incident.
“Our thoughts are with the family and friends of the woman and child who have died, and also with the officers and paramedics who were first to arrive at what was an incredibly challenging scene.
“Specialist detectives are working to establish what took place and a man is in custody.
“While they are keeping an open mind as to what has taken place, I would like to reassure residents in the local area that there is nothing to indicate, at this stage, that anyone else was involved in this incident.
“I would urge anyone who saw or heard anything unusual earlier today, or in recent days, to come forward and speak to the police. Your information could be vital as the investigation moves forward.”
Information can be provided to police by calling 101 with the reference 3590/21JUN.
Alternatively, it can be provided to the independent charity Crimestoppers, anonymously, on 0800 555 111.