Four people have been arrested on suspicious of corporate manslaughter following the death of a worker who fell through a roof near Wembley Stadium.
Reza Alipour, 41, died at the scene despite receiving first aid from the emergency services.
He had fallen from height while employed at a building owned by a fine art and antique buyer.
Metropolitan Police detectives have launched a homicide investigation.
Officers are appealing for anyone to come forward with information on Mr Alipour’s death at Latif House in First Way, Wembley at 2.30pm on Thursday, May 11.
A 45-year-old man was arrested for alleged corporate manslaughter last week Friday.
The following day, two other men and a woman were detained for the same offence.
All have been bailed pending further enquiries until August.
Scotland Yard said: “Officers attended along with the London Ambulance Service and London’s Air Ambulance. Despite their efforts, a 41-year-old man died at the scene.
“His next of kin have been informed.
“The death is being treated as unexplained and a post-mortem examination is due to take place.
“Detectives from the Met’s Specialist Crime Command are leading the investigation and enquiries are ongoing.”
A London Ambulance Service spokesman said: “We sent numerous resources to the scene, including an ambulance crew, a medic in a fast response car, an incident response officer and a clinical team manager. We also dispatched London’s Air Ambulance.
“Sadly, despite the best efforts of our crews, a man was pronounced dead at the scene.”
Brent Council confirmed the building is privately owned by a company known as Latif Group. The firm, trading as Latif International, did not respond to requests for comment.
The Health and Safety Executive added: “We are aware of an incident and making enquiries with the Metropolitan Police led investigation.”
