Officers investigation the stabbing have arrested a 26-year-old man on suspicion of murder who is being held in police custody at a station in north London.
Emergency services were called to the Halifax branch in Wealdstone High Street at around 6.50pm after reports of a stabbing.
Mr Al-Zufairi, 34, died at around 2.30am on Tuesday morning (February 28).
Detective Chief Inspector Mark Lawson, who is leading the investigation, said: “We know that the area at the time of the stabbing, just before 6.50pm, would have been very busy with people coming from nearby Harrow and Wealdstone station.
"Other people would have been shopping at the time.
"We are very keen to hear from anyone who was in and around the Wealdstone High Street area that may have seen or heard anything suspicious, especially from anyone who saw people running towards the station.”
The victim has not been formally identified but the Metropolitan Police are satisfied that he is Mohamed Al-Zufairi, it said.
A post-mortem examination was due to take place at Northwick Park Hospital on Wednesday (March 1).
His next of kin have been informed.
Any witnesses or anyone with any information, are urged to contact the incident room on 020 8358 0200, or contact police by calling 101 or by tweeting @MetCC
To give information anonymously contact Crimestoppers on 0800 555 111 or visit crimestoppers-uk.org.
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