Police say they received a number of calls about the incident and found three people injured.
Image source, Essex Police
Eight people have been arrested on suspicion of murder after two teenage boys died.
Essex Police said officers found three people injured after receiving a number of calls to Regency Court, Brentwood, at about 01:30 BST.
Two of those had since died, the force said, while the third was treated for non-life threatening injuries.
Police said they were “working to establish how the boys died” and post-mortem examinations would take place.
Det Ch Insp Andy Clarkson, of the Kent and Essex Serious Crime Directorate, said: “We understand there will naturally be shock and concern within the community after such a tragic loss of life.
“But, at this stage, we do not believe there is any wider threat to the public.”
Image source, Essex Police
The detective said the incident “required an immediate and a large-scale response” and that investigations would continue throughout Sunday.
He added: “We know there were a number of witnesses to this incident and I would urge anyone who saw anything in Regency Court and the roads around it in central Brentwood between 01:00 and 02:00 to come forward and speak to us if you have not already done so.”
Image source, Essex Police
Ch Insp Mark Barber added there would be a “highly-visible police presence” in Brentwood on Sunday.
“I am acutely aware that this incident will shock many within the community,” he said. “My officers will be there throughout the day – they will be there to reassure you and keep you safe.
“If you have any concerns or information on the incident then, please, do not hesitate to come forward and speak to them.”
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