A 20-year-old man has been arrested on suspicion of murder in connection with a fatal stabbing in Walthamstow.

The victim, a man aged in his 30s, died in the arms of paramedics in Ulverston Road near the junction with Forest Road just after 5pm on Monday (May 21).

He has not been formally identified.

In a statement this lunchtime, Scotland Yard said the arrested man was being quizzed at Lewisham Police Station but had not been charged.

A post mortem held yesterday (Tuesday May 22) concluded the man died of a stab wound to the heart.

A police spokeswoman said there were "a lot of unknowns" surrounding the case.

Detectives are keeping an open mind over the motive but the area is not known for gang activity.

The victim is thought to have staggered through several streets before flagging down a passing policeman for help.

His family live abroad and police have so far been unable to contact them to tell them the news.

Acting borough commander Supt. Adrian Hutchinson paid tribute to police who initially treated the man at the scene.

He said: "The officer did everything he could to save the man's life until paramedics arrived, something which was witnessed by the community.

"I want to reassure residents we have extra officers on the ground and are working very hard on this case."

Police closed off a large area of Upper Walthamstow and Forest Road between Wood Street and Woodford New Road following the stabbing.

It was not reopened until after 9am the next day, prompting complaints about disruption.

Supt. Hutchinson said he was surprised by the reaction from some residents who commented on the Guardian's website criticising the closures.

He said: "We appreciate that the cordon was large and did cause some disruption, but its size was a necessity for forensic retrieval.

"The victim moved after being stabbed and everywhere he went became a crime scene.

"Our first priority was the victim and getting him medical help, but we still notified the transport authorities and media within an hour".

A Met spokeswoman added: "While this was a distressing event they are still quite a rare occurrence in this borough.

"Safer Neighbourhoods Teams have been leafleting the community and we have extra resources and patrols in place."

An incident room has been opened by police at the Met's Homicide and Serious Crime Command at Lewisham.

Any witnesses or anyone with information is urged to call 020 8721 4906.

To remain anonymous call Crimestoppers on 0800 555 111.

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