INVESTIGATORS have admitted they will never know the exact cause of the Rosehill Street explosion.
The Health and Safety Executive has closed the investigation into the gas blast which destroyed three houses and seriously damaged seven others.
A spokesman said: "We could find no definitive cause for the explosion.
"The nature of the explosion meant it was difficult to carry out a forensic exploration of the site and we have been unable to find any evidence of recent work or a fault in any gas appliance."
He added: "The catastrophic seriousness of the explosion itself made it very difficult to piece together physical evidence of how it is most likely to have been caused.
"With regards to the way evidence was removed and stored, the investigators did the very best they could in the circumstances of the evidence lying in the wreckage of the explosion.
"The evidence was obtained as early as possible, was handled, stored and transported in the best practicable manner and has been scrutinised fairly and thoroughly."
When the explosion tore through number 34 Rosehill Street on May 10 last year, the blast could be heard as far as three miles away.
Residents in the surrounding houses thought a bomb had gone off or a plane had crashed.
There was a thunderous blast, the ground shook violently, doors were blown off their hinges and windows were shattered.
When they looked outside, they were confronted by the sight of a pile of smoking rubble where number 34 had once stood and the jagged half-collapsed structures of the houses either side.
Despite their horror, they made their way into the street – some having to force their way out through warped doorframes and smashed windows – to do what they could to help the injured in the destroyed houses.
The emergency services arrived on the scene within minutes, evacuating the area so the rescue mission could begin, and they soon realised that, miraculously, nobody had been seriously injured.
However, number 34 and the houses either side had to be completely demolished afterwards. Seven other properties were deemed unsafe, meaning the residents had to live elsewhere while their homes were repaired, but most have now moved back to the street.
