A Chippenham firm at the centre of an investigation into the gas explosion which destroyed a pensioner's house will not be prosecuted.

The Health and Safety Executive revealed yesterday that there will be no criminal charges brought against Wales and West Utilities or its sub contractors, Chippenham company Avent Engineering of the Bath Road Industrial Estate.

A Health and Safety Executive spokesman confirmed the blast occurred after a mains gas pipe was connected to a disused open-ended pipe that ran under Jimmy Brown's home in The Horsefair.

When Mr Brown, 77, lit his gas stove he sparked the explosion.

The spokesman said: "The Avent contractor was trying to connect the new main gas pipe to Mr Brown's individual gas pipe.

"But the pipe they connected to the main pipe was open ended and ran under Mr Brown's kitchen pouring mains gas under the floorboards.

"The pipe was an old disused pipe.

We are doubtful a standard pressure test was carried out but we cannot prove this."

Avent managing director Michael Snees said: "Avent Engineering will not be prosecuted but have agreed actions with the Health & Safety Executive to address audit and roles and responsibilities in regard to this activity.It is worth nothing that the individuals responsible for the work activity at The Horsefair are no longer working for the company."