Police have arrested a 32-year-old man on suspicion of manslaughter following the death of two-year-old Jamie Heaton at a house explosion in Shaw, Oldham.
Jamie was watching TV in his home when he was killed by the blast, which ripped through three terraces houses and caused damage to several others nearby at 11.15am on 26 June.
Police are also wanting to speak to 27-year-old Andrew Partington, who is recovering in hospital after suffering from life-threating burns following the blast on Buckley Street.
The National Grid confirmed the explosion was not caused by a gas pipe leak and Greater Manchester Police (GMP) have now launched a murder investigation.
In a statement, the Heaton family said: "Jamie's life was full of laughter. He loved going to pre-school, playing with sand and water and going to the park. He touched the hearts of all who knew him and will be missed by all."
Jamie's mother survived the blast as she was In the backyard of the house hanging up clothes. Her husband and two other children were not at home at the time of the blast.
Assistant Chief Constable Steve Heywood, from Greater Manchester Police, said: "We've had information to suggest that it might not have been accidental, so we are treating it as a suspicious death and, therefore, a homicide investigation is being undertaken."
Heywood also compared the scene to the aftermath of a bomb explosion.
He added: "Being local to the Oldham area, I am personally saddened by this incident, which has claimed the life of a young and much loved boy and brought scenes of devastation to Shaw. "It looks like there has been a bomb.
"It looks like the Manchester bomb site. It looks devastated. As tragic as this incident is, I take heart from the overwhelming response from the local community and businesses, all of whom have shown great strength in adversity, and GMP and our partners will continue to support them in whatever way we can.
Police have said they also have "significant questions" to neighbour Partington when recovers from his injuries.
Partington, who is not related to Jamie, was taken to Wythenshawe Hospital where police say is he "unconscious and sedated".
Police confirmed that Partington's partner, locally named as Tanya Williamson, and her five children were in another town when the explosion happened.
It has been reported the pair had an argument the night before the explosion and Williamson and her children had gone to her sister's house.
The blast destroyed number 11 Buckley Street, where Jamie lived, and number nine, the home of Partington.
It is understood Partington had only moved into the address around six weeks ago.