A man in his forties and a five-year-old boy were found dead in a house in Leicester on Monday night.
Emergency services, including an air ambulance, were called to the address in Hopyard Close at around 9:00 pm after the two were found unconscious.
Despite the efforts of the East Midlands Ambulance Service and the air ambulance, both were pronounced dead at the scene.
Leicestershire Police has launched an investigation into the deaths but stated that there is no risk to the public.
The families of the man and boy are being supported by police.
The house remains cordoned off while inquiries continue.
Det Ch Insp Mark Sinski, from the East Midlands Special Operations Unit major crime team, said that detectives are working to understand what happened inside the address.
Alan Potter, a 75-year-old neighbor, said he heard the boy running around before bedtime at around 6:00 or 7:00 pm.
Emergency services arrived at around 10:30 pm, with police and ambulance personnel dashing in and out of the house.
Carole Potter, 70, said the news was "tragic" and that the family were "great friends" with the boy's mother.
She added that they treated the boy like he was her own grandson.
Wayne Hurst, a 51-year-old neighbor, described seeing a "load of ambulances" and police cars on Monday night.
He said he was "shocked" and "scared" by the incident.
This tragic event has left the community in shock and mourning.
Leicestershire Police is urging anyone with information to come forward and assist with their investigation.
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