Police are not ruling out a possible link between a fatal house fire near Middlesbrough and a crash on the A66 less than two miles away that killed seven people.
Officers have launched a murder investigation after two people died in a blaze on Birchington Avenue, Grangetown, on Wednesday morning.
Four other people were injured, including a woman who is said to be in a critical condition.
The blaze happened less two miles from the scene of a crash on Sunday between a VW Passat, which was heading in the wrong direction on the dual-carriageway, and a marked police armed response vehicle.
Pc Matthew Blades, 37, and Pc Tom Clough, 38, were killed in the collision.
The five people in the Passat – Cole Worthy, 17, Theo Rae, 17, Makai Saddington, 18, and 23-year-olds Michael Robert Cahill and Jacob Matusiak – were pronounced dead at the scene at South Bank.
Cleveland Police are not ruling out a link between the two incidents, and said they “cannot rule out any links to wider organised crime at this time”.
Officers were called to the fire just before 5.30am on Wednesday, with two people later confirmed dead.
A woman remains in the Royal Victoria Infirmary in Newcastle in a critical condition, and a further three people suffered non-life-threatening injuries.
They are currently receiving treatment in hospital.
Redcar and Cleveland Local Policing Commander, Superintendent Emily Harrison, said: “This is a tragic incident which has sadly resulted in the deaths of a number of people this morning, and their families are being supported by specially trained officers.
“We are working to establish the circumstances of exactly what has happened, but we are keeping an open mind and cannot rule out any links to wider organised crime at this time.
“We will have a high visibility presence in the Grangetown area as this investigation progresses, and to provide reassurance to local communities, who will no doubt be impacted by this tragic incident.
“We encourage anyone who has concerns, or who may have information regarding the incident in the early hours of this morning, to approach one of our officers or to contact Cleveland Police on 101, or Crimestoppers anonymously.”
Cleveland Fire Brigade said they sent six fire engines and the Incident Command Unit to the scene.
A spokesperson said road closures were in place in the surrounding area and asked members of the public to avoid the area where possible.
Redcar & Cleveland borough councillor for Grangetown Adam Brook said the fire was “absolutely devastating”, but urged people not to speculate or “share unconfirmed information”.
He said: “Many residents have been in touch with me throughout the morning, and I know there is understandably a great deal of concern.
“However, I would urge people not to speculate or share unconfirmed information.”
Mr Brook added: “At this stage I don’t want to speculate or comment on any information that has not been officially confirmed while the emergency services continue their work.”
Cleveland Police have arrested 17 people following the crash on Sunday.
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