Reports said the police had found something, but were not sure what it was. Given the heightened security concerns at the moment they obviously wanted to be cautious.
The public were then requested to move even further back, heightening the tension.
Specialist from the fire brigade entered the building and took readings but did not find anything suspicious.
Shortly after midday, the cordoned off area was reduced and the public were allowed to return to West End Lane.
By 12.30 the alarm was over. The police were satisfied that the smell was not harmful and West End Lane was reopened shortly after.
Subsequent investigation may have got to the bottom of it. The possible source of the smell may have been a building site portaloo on neighbouring Mill Lane, which was emptied that morning.